Supplement WB.14: Case Study - Parts 1 & 2: Ti and Carli [New Tab]<\/a><\/div>\nUnderstanding the Lazarus Appraisal Model of Stress<\/h1>\nThe limitations of both the stimulus-based and response-based definitions lead us to consider a more comprehensive model of stress: the Lazarus Appraisal Model<\/strong>. Developed by Lazarus & Folkman in 1984, this model emphasises the role of individual appraisal in the experience of stress. It suggests that stress is not solely determined by external events or physiological responses but also by the ways an individual interprets and reacts to these events.\n
Understanding the Lazarus Appraisal Model of Stress<\/h1>\nThe limitations of both the stimulus-based and response-based definitions lead us to consider a more comprehensive model of stress: the Lazarus Appraisal Model<\/strong>. Developed by Lazarus & Folkman in 1984, this model emphasises the role of individual appraisal in the experience of stress. It suggests that stress is not solely determined by external events or physiological responses but also by the ways an individual interprets and reacts to these events.\nPrimary and Secondary Appraisal<\/h2>\nThe process begins with what is known as primary appraisal<\/strong>, where an individual assesses the potential harm or threat a stressor might pose to their well-being. In the previous example of Ti and Carli (Supplement WB.14), the stressor was leaving home to move into university residence. The primary appraisal involves evaluating whether a situation or event is a threat, which could lead to harm, loss, or other negative consequences. Conversely, the same situation can be appraised as a challenge, presenting an opportunity for overcoming fear or demonstrating courage.\n\nSecondary appraisal<\/strong> follows, where the individual assesses their ability to cope with the stressor, considering the resources they have at hand. This appraisal involves determining how effectively one can manage or adapt to the stressor. The perception of one's ability to handle the situation influences whether it is viewed as a manageable challenge or a significant threat.<\/a>\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"]![\"A](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/02\/SH-Stress-Concept-Map.jpeg\" "\\"A")
Figure WB.6. Primary and secondary appraisal.<\/strong> When encountering a stressor, a person judges its potential threat (primary appraisal) and then determines if effective options are available to manage the situation. Stress is likely to result if a stressor is perceived as extremely threatening or threatening with few or no effective coping options available. [Image Description]<\/em><\/a>[\/caption]After exploring the stimulus-based and response-based definitions through the experiences of Ti and Carli, let's delve deeper into the Lazarus appraisal model with a different scenario. This will help us further understand how individual perceptions significantly influence stress responses.\n\nFacing Fido in the Forest: Another Walk Through the Lazarus Model<\/h2>\n<\/header>\n\n\nLet's walk through the Lazarus model decision tree using the example of you hiking along a forest path when you suddenly encounter a large, loudly barking dog on a forest path. This model involves two key stages of appraisal: primary and secondary.\nPrimary appraisal<\/h3>\nIn the primary appraisal stage, you assess the situation to determine if the large, barking dog poses a threat to your well-being or if it represents a challenge.\n\n \t- Perceived as a threat<\/strong>: If you perceive the dog as dangerous (due to its size, loud bark, and the isolated forest setting), you might appraise this situation as a threat. This perception could be based on past experiences, inherent fears of dogs, or the unexpected nature of the encounter. You anticipate potential harm or danger from the dog.<\/li>\n \t
- Perceived as a challenge<\/strong>: Alternatively, you might perceive the encounter with the dog as a challenge. This could occur if you view the situation as an opportunity to overcome a fear of dogs or to demonstrate courage in handling unexpected situations. Your focus here is on the potential for personal growth or mastery in dealing with the situation.<\/li>\n<\/ul>\n
Secondary appraisal<\/h3>\nIn the secondary appraisal stage, you evaluate your coping resources and options to handle the situation with the dog.\n\n \t- Ineffective or no coping options available (perceived as a threat)<\/strong>: If, on the other hand, you feel you lack the resources to deal with the dog (due to a lack of experience with dogs, absence of any means to protect yourself, or being alone in the forest), you might view the situation as a significant threat to your safety. This perception leads to a higher level of stress and potential feelings of helplessness or fear.<\/li>\n \t
- Effective coping options available (perceived as a challenge)<\/strong>: If you feel confident in your ability to handle the situation (perhaps due to previous positive experiences with dogs, knowledge about animal behaviour, or the presence of tools like a walking stick), you might view the encounter as a manageable challenge. You believe you have the necessary resources and strategies to safely navigate the situation.<\/li>\n<\/ul>\n
Outcome based on appraisal<\/h3>\n\n \t- High stress (threat perception with ineffective coping)<\/strong>: If you appraise the dog as a threat and feel you cannot effectively cope with the situation, you are likely to experience a high level of stress. This stress could manifest as fear, anxiety, and physiological responses like increased heart rate or adrenaline rush.<\/li>\n \t
- Low to moderate stress (challenge perception with effective coping)<\/strong>: If you appraise the situation as a challenge and feel capable of handling it, your stress level may be lower or even positive in nature, characterised by a sense of alertness and readiness to act.<\/li>\n<\/ul>\nIn summary, according to the Lazarus model, your experience of stress in encountering the barking dog on a forest path is determined not just by the presence of the dog (the external stimulus) but significantly by how you appraise the situation (threat or challenge) and your perceived ability to cope with it. This model underscores the subjective nature of stress and the importance of individual perception and evaluation in stress experiences.\n\n<\/div>\n<\/div>\nHaving navigated the Lazarus model with the example of the hiker and the barking dog, we can see how individual appraisal plays a crucial role in the experience of stress.\n\nThis understanding brings us back to Ti and Carli, whose experiences we can now re-examine through the lens of this model.\nSupplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"]![\"A](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/SH4-Optimal-Stress.jpeg\" "\\"A")
Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"]![\"A](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/img8.10.png\" "\\"A")
Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"]![\"A](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/img8.11.png\")
Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"]
![\"An](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/SH7-Fight-or-Flight-768x430-1.jpeg\" "\\"An")
Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\nSelye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"]![\"A](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/SH9-General-Adaptation-Syndrome.jpeg\" "\\"A")
Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"]![\"The](\"https:\/\/opentextbc.ca\/psychologymtdi\/wp-content\/uploads\/sites\/470\/2024\/08\/SH10-HPA.jpeg\" "\\"The")
Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Figure WB.6. Primary and secondary appraisal.<\/strong> When encountering a stressor, a person judges its potential threat (primary appraisal) and then determines if effective options are available to manage the situation. Stress is likely to result if a stressor is perceived as extremely threatening or threatening with few or no effective coping options available. [Image Description]<\/em><\/a>[\/caption]After exploring the stimulus-based and response-based definitions through the experiences of Ti and Carli, let's delve deeper into the Lazarus appraisal model with a different scenario. This will help us further understand how individual perceptions significantly influence stress responses.\nFacing Fido in the Forest: Another Walk Through the Lazarus Model<\/h2>\n<\/header>\n\n\nLet's walk through the Lazarus model decision tree using the example of you hiking along a forest path when you suddenly encounter a large, loudly barking dog on a forest path. This model involves two key stages of appraisal: primary and secondary.\nPrimary appraisal<\/h3>\nIn the primary appraisal stage, you assess the situation to determine if the large, barking dog poses a threat to your well-being or if it represents a challenge.\n\n \t- Perceived as a threat<\/strong>: If you perceive the dog as dangerous (due to its size, loud bark, and the isolated forest setting), you might appraise this situation as a threat. This perception could be based on past experiences, inherent fears of dogs, or the unexpected nature of the encounter. You anticipate potential harm or danger from the dog.<\/li>\n \t
- Perceived as a challenge<\/strong>: Alternatively, you might perceive the encounter with the dog as a challenge. This could occur if you view the situation as an opportunity to overcome a fear of dogs or to demonstrate courage in handling unexpected situations. Your focus here is on the potential for personal growth or mastery in dealing with the situation.<\/li>\n<\/ul>\n
Secondary appraisal<\/h3>\nIn the secondary appraisal stage, you evaluate your coping resources and options to handle the situation with the dog.\n\n \t- Ineffective or no coping options available (perceived as a threat)<\/strong>: If, on the other hand, you feel you lack the resources to deal with the dog (due to a lack of experience with dogs, absence of any means to protect yourself, or being alone in the forest), you might view the situation as a significant threat to your safety. This perception leads to a higher level of stress and potential feelings of helplessness or fear.<\/li>\n \t
- Effective coping options available (perceived as a challenge)<\/strong>: If you feel confident in your ability to handle the situation (perhaps due to previous positive experiences with dogs, knowledge about animal behaviour, or the presence of tools like a walking stick), you might view the encounter as a manageable challenge. You believe you have the necessary resources and strategies to safely navigate the situation.<\/li>\n<\/ul>\n
Outcome based on appraisal<\/h3>\n\n \t- High stress (threat perception with ineffective coping)<\/strong>: If you appraise the dog as a threat and feel you cannot effectively cope with the situation, you are likely to experience a high level of stress. This stress could manifest as fear, anxiety, and physiological responses like increased heart rate or adrenaline rush.<\/li>\n \t
- Low to moderate stress (challenge perception with effective coping)<\/strong>: If you appraise the situation as a challenge and feel capable of handling it, your stress level may be lower or even positive in nature, characterised by a sense of alertness and readiness to act.<\/li>\n<\/ul>\nIn summary, according to the Lazarus model, your experience of stress in encountering the barking dog on a forest path is determined not just by the presence of the dog (the external stimulus) but significantly by how you appraise the situation (threat or challenge) and your perceived ability to cope with it. This model underscores the subjective nature of stress and the importance of individual perception and evaluation in stress experiences.\n\n<\/div>\n<\/div>\nHaving navigated the Lazarus model with the example of the hiker and the barking dog, we can see how individual appraisal plays a crucial role in the experience of stress.\n\nThis understanding brings us back to Ti and Carli, whose experiences we can now re-examine through the lens of this model.\nSupplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Primary appraisal<\/h3>\nIn the primary appraisal stage, you assess the situation to determine if the large, barking dog poses a threat to your well-being or if it represents a challenge.\n\n \t- Perceived as a threat<\/strong>: If you perceive the dog as dangerous (due to its size, loud bark, and the isolated forest setting), you might appraise this situation as a threat. This perception could be based on past experiences, inherent fears of dogs, or the unexpected nature of the encounter. You anticipate potential harm or danger from the dog.<\/li>\n \t
- Perceived as a challenge<\/strong>: Alternatively, you might perceive the encounter with the dog as a challenge. This could occur if you view the situation as an opportunity to overcome a fear of dogs or to demonstrate courage in handling unexpected situations. Your focus here is on the potential for personal growth or mastery in dealing with the situation.<\/li>\n<\/ul>\n
Secondary appraisal<\/h3>\nIn the secondary appraisal stage, you evaluate your coping resources and options to handle the situation with the dog.\n\n \t- Ineffective or no coping options available (perceived as a threat)<\/strong>: If, on the other hand, you feel you lack the resources to deal with the dog (due to a lack of experience with dogs, absence of any means to protect yourself, or being alone in the forest), you might view the situation as a significant threat to your safety. This perception leads to a higher level of stress and potential feelings of helplessness or fear.<\/li>\n \t
- Effective coping options available (perceived as a challenge)<\/strong>: If you feel confident in your ability to handle the situation (perhaps due to previous positive experiences with dogs, knowledge about animal behaviour, or the presence of tools like a walking stick), you might view the encounter as a manageable challenge. You believe you have the necessary resources and strategies to safely navigate the situation.<\/li>\n<\/ul>\n
Outcome based on appraisal<\/h3>\n\n \t- High stress (threat perception with ineffective coping)<\/strong>: If you appraise the dog as a threat and feel you cannot effectively cope with the situation, you are likely to experience a high level of stress. This stress could manifest as fear, anxiety, and physiological responses like increased heart rate or adrenaline rush.<\/li>\n \t
- Low to moderate stress (challenge perception with effective coping)<\/strong>: If you appraise the situation as a challenge and feel capable of handling it, your stress level may be lower or even positive in nature, characterised by a sense of alertness and readiness to act.<\/li>\n<\/ul>\nIn summary, according to the Lazarus model, your experience of stress in encountering the barking dog on a forest path is determined not just by the presence of the dog (the external stimulus) but significantly by how you appraise the situation (threat or challenge) and your perceived ability to cope with it. This model underscores the subjective nature of stress and the importance of individual perception and evaluation in stress experiences.\n\n<\/div>\n<\/div>\nHaving navigated the Lazarus model with the example of the hiker and the barking dog, we can see how individual appraisal plays a crucial role in the experience of stress.\n\nThis understanding brings us back to Ti and Carli, whose experiences we can now re-examine through the lens of this model.\nSupplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Secondary appraisal<\/h3>\nIn the secondary appraisal stage, you evaluate your coping resources and options to handle the situation with the dog.\n\n \t- Ineffective or no coping options available (perceived as a threat)<\/strong>: If, on the other hand, you feel you lack the resources to deal with the dog (due to a lack of experience with dogs, absence of any means to protect yourself, or being alone in the forest), you might view the situation as a significant threat to your safety. This perception leads to a higher level of stress and potential feelings of helplessness or fear.<\/li>\n \t
- Effective coping options available (perceived as a challenge)<\/strong>: If you feel confident in your ability to handle the situation (perhaps due to previous positive experiences with dogs, knowledge about animal behaviour, or the presence of tools like a walking stick), you might view the encounter as a manageable challenge. You believe you have the necessary resources and strategies to safely navigate the situation.<\/li>\n<\/ul>\n
Outcome based on appraisal<\/h3>\n\n \t- High stress (threat perception with ineffective coping)<\/strong>: If you appraise the dog as a threat and feel you cannot effectively cope with the situation, you are likely to experience a high level of stress. This stress could manifest as fear, anxiety, and physiological responses like increased heart rate or adrenaline rush.<\/li>\n \t
- Low to moderate stress (challenge perception with effective coping)<\/strong>: If you appraise the situation as a challenge and feel capable of handling it, your stress level may be lower or even positive in nature, characterised by a sense of alertness and readiness to act.<\/li>\n<\/ul>\nIn summary, according to the Lazarus model, your experience of stress in encountering the barking dog on a forest path is determined not just by the presence of the dog (the external stimulus) but significantly by how you appraise the situation (threat or challenge) and your perceived ability to cope with it. This model underscores the subjective nature of stress and the importance of individual perception and evaluation in stress experiences.\n\n<\/div>\n<\/div>\nHaving navigated the Lazarus model with the example of the hiker and the barking dog, we can see how individual appraisal plays a crucial role in the experience of stress.\n\nThis understanding brings us back to Ti and Carli, whose experiences we can now re-examine through the lens of this model.\nSupplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Outcome based on appraisal<\/h3>\n\n \t- High stress (threat perception with ineffective coping)<\/strong>: If you appraise the dog as a threat and feel you cannot effectively cope with the situation, you are likely to experience a high level of stress. This stress could manifest as fear, anxiety, and physiological responses like increased heart rate or adrenaline rush.<\/li>\n \t
- Low to moderate stress (challenge perception with effective coping)<\/strong>: If you appraise the situation as a challenge and feel capable of handling it, your stress level may be lower or even positive in nature, characterised by a sense of alertness and readiness to act.<\/li>\n<\/ul>\nIn summary, according to the Lazarus model, your experience of stress in encountering the barking dog on a forest path is determined not just by the presence of the dog (the external stimulus) but significantly by how you appraise the situation (threat or challenge) and your perceived ability to cope with it. This model underscores the subjective nature of stress and the importance of individual perception and evaluation in stress experiences.\n\n<\/div>\n<\/div>\nHaving navigated the Lazarus model with the example of the hiker and the barking dog, we can see how individual appraisal plays a crucial role in the experience of stress.\n\nThis understanding brings us back to Ti and Carli, whose experiences we can now re-examine through the lens of this model.\nSupplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Supplement WB.15: Case Study - Lazarus Model Analysis Ti and Carli [New Tab]<\/a><\/div>\nIn summary, if a person appraises an event as harmful and believes that the demands imposed by the event exceed the available resources to manage or adapt to it, they will subjectively experience a state of stress. Conversely, if one does not appraise the same event as harmful or threatening, they are unlikely to experience stress. According to this definition, environmental events trigger stress reactions by the way they are interpreted and the meanings they are assigned. In short, stress is largely in the eye of the beholder: it\u2019s not so much what happens to you as how you respond (Selye, 1976).\nStress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\n
Stress: The Good and the Bad<\/h1>\nStress is often seen as something negative, but it can also be helpful. Stress can push us to do important things like study for exams, go to the doctor, exercise, and work hard. Selye, a scientist in 1974, said that stress isn't always bad. He explained that stress can be a good thing that helps improve our lives. He called this good stress \"eustress\" (from a Greek word meaning \u201cgood\u201d). Eustress<\/strong> is the kind of stress that makes you feel positive and can be good for your health and performance.\nStress manifests in two primary forms: eustress<\/strong>, which is positive and can motivate and energise us, leading to improved performance and well-being, and distress<\/strong>, which is negative, overwhelming, and can lead to burnout, decreased performance, and health issues. Understanding the difference between these two types of stress is crucial for managing stress effectively, allowing us to harness the motivating aspects of eustress while minimising the harmful effects of distress on our mental and physical health. Eustress can make you do better and feel good; distress can make you do worse and harm your health.<\/div>\nA moderate amount of stress can be beneficial in challenging situations. For example, athletes may be motivated and energised by pre-game stress, and students may experience similar beneficial stress before a major exam. Indeed, research shows that moderate stress can enhance both immediate and delayed recall of educational material. Male participants in one study who memorised a scientific text passage showed improved memory of the passage immediately after exposure to a mild stressor as well as one day following exposure to the stressor (Hupbach & Fieman, 2012).\n\nBut when stress exceeds this optimal level, it is no longer a positive force; it becomes excessive and debilitating, or what Selye termed distress<\/strong> (from the Latin dis = \u201cbad\u201d). People who reach this level of stress feel burned out; they are fatigued and exhausted, and their performance begins to decline. If the stress level remains excessive, health may begin to erode as well (Everly & Lating, 2002).\nStress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Stress and Performance<\/h2>\nFigure WB.7\u00a0shows us that as stress increases, so does performance and well-being, up to a point. This is eustress. When stress reaches the best level (the highest point of a curve), performance is at its best. You feel fully energised and focused, and you work efficiently. But if stress goes beyond this best level, it becomes too much and harmful; this is distress. People with too much stress feel burned out and tired, and their performance drops. If the stress level stays too high, it can even harm health. For example, students who are very stressed about a test might find it hard to concentrate, which can affect their test scores.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.7. Stress and performance.<\/strong> As the stress level increases from low to moderate, so does performance (eustress). At the optimal level (the peak of the curve), performance has reached its peak. If stress exceeds the optimal level, it will reach the distress region, where it will become excessive and debilitating, and performance will decline (Everly & Lating, 2002).[\/caption]\n\nA graph features a bell curve that has a line going through the middle labeled \u201cOptimal level.\u201d The curve is labelled \u201ceustress\u201d on the left side and \u201cdistress\u201d on the right side. The x-axis is labeled \u201cStress level\u201d and moves from low to high, and the y-axis is labeled \u201cPerformance level\u201d and moves from low to high.\u201d The graph shows that stress levels increase with performance levels and that once stress levels reach optimal level, they move from eustress to distress.\nStress in Our Lives<\/h2>\nStress is a common experience. We all deal with it in different ways. It can feel like a heavy load, like when you have to drive in a blizzard, wake up late for an important job interview, run out of money, or aren't ready for a big test. Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions. We may react to stress in unhealthy ways by drinking alcohol, smoking, or engaging in other dubious behaviours we hope will reduce the stress. While stress can sometimes be good, it can also lead to health problems, contributing to illnesses and diseases. Stress can cause physical reactions like a fast heartbeat or headaches, make it hard to think or decide, and lead to behaviours like drinking or smoking.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Figure WB.8. Driving during a blizzard.<\/strong> Stress is an experience that can include symptoms like a faster heart rate, headaches, gastrointestinal problems, and difficulty concentrating or making decisions.[\/caption]\nHealth Psychology and Stress<\/h2>\nThe scientific study of how stress and other psychological factors impact health is part of health psychology. Health psychology is a subfield of psychology that focuses on understanding the importance of psychological influences on health and illness, and how people respond when they become ill (Taylor, 1999). Health psychology emerged as a discipline in the 1970s, a time of increasing awareness of the role behavioural and lifestyle factors play in the development of illnesses and diseases (Straub, 2007). In addition to studying the connection between stress and illness, health psychologists investigate issues such as the reasons people make certain lifestyle choices, e.g., smoking or eating unhealthy food, despite knowing the potential adverse health implications of such behaviours.\n\nHealth psychologists also work on creating and testing ways to help people change unhealthy behaviours. A key part of their job is to figure out which groups of people are more likely to have health problems because of the way they think or act. For instance, they might study how stress affects different age groups, like young adults versus older adults. By understanding who gets more stressed and how it changes over time, health psychologists can identify which age group might be more at risk for health issues like high blood pressure or anxiety disorders.\n\nWatch this video: The Upside of Stress (4.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=sZtEwEIUIOc\n\n\u201cThe Upside of Stress\u201d video by BrainCraft is licensed under the Standard YouTube licence.<\/span>\nCannon and the Fight-or-Flight Response<\/h1>\nStress, a universal experience, has intrigued scientists for nearly a century. A key figure in this exploration is Walter Cannon, an American physiologist whose groundbreaking work in the early 20th century has significantly shaped our understanding of how the body reacts to stress. Cannon's insights into the fight-or-flight response have provided a foundational understanding of the body's physiological mechanisms when confronted with stress.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"350\"] Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n\n \t- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\nContent Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"] Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\nSupplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\nSupplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n
Figure WB.9. Flight-or-fight response.<\/strong> A dog jumps onto the path, barking and giving mixed signals. Is it going to bite you or just saying hello? Your fight-or-flight response will likely kick in to give you extra alertness and energy to deal with the possible threat.[\/caption]\n\nTo illustrate Cannon's fight-or-flight model, let's return to our previous scenario, imagine you are back again, hiking in a forest when suddenly a large, barking dog appears. The dog, emerging from behind a stand of trees, stops about 50 yards from you. It notices you, barks louder, and starts moving in your direction. You think, \u201cThis is definitely not good,\u201d and experience a series of physical reactions:\n- \n \t
- Your pupils dilate.<\/li>\n \t
- Your heart races and speeds up.<\/li>\n \t
- You start breathing heavily and sweating.<\/li>\n \t
- You feel butterflies in your stomach.<\/li>\n \t
- Your muscles tense up, readying you to take action.<\/li>\n<\/ul>\nCannon proposed that this reaction, termed the fight-or-flight response<\/strong>, occurs when a person experiences intense emotions, especially those associated with a perceived threat (Cannon, 1932). During the fight-or-flight response, the body is rapidly aroused by the activation of both the sympathetic nervous system and the endocrine system (Figure WB.10). This arousal prepares the person to either confront or escape the perceived threat.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"768\"] Figure WB.10. Fight-or-flight response in the body.<\/strong> This diagram illustrates the fight-or-flight response, showing a human body and highlighting various physiological reactions, such as increased heart rate, dilated pupils, and quickened respiration.[\/caption]\n\nIn conclusion, Cannon's concept of the fight-or-flight response has been instrumental in advancing our understanding of stress physiology. By identifying the body's innate mechanism for maintaining homeostasis in the face of threats, Cannon's work has laid the groundwork for further research into how we respond to stress. This response, crucial for survival, highlights the body's remarkable ability to adapt to and manage challenging situations, a testament to the complex\u00a0 and dynamic nature of human physiology.\n\nHaving explored Cannon's pivotal work on the immediate, fight-or-flight response to stress, we now turn to another seminal figure in stress research, Hans Selye. While Cannon focused on the body's acute reaction to stress, Selye's work delves into the prolonged effects of stress on the body. His concept of the General Adaptation Syndrome (GAS) offers a broader perspective, examining how our bodies cope with sustained stress over time. This shift from the immediate to the enduring effects of stress marks a significant development in our understanding of how stress impacts us.\n
Selye and the General Adaptation Syndrome<\/h1>\n
Content Disclosure: <\/strong>This section discusses historical research methods involving animal testing that are now considered unethical. These studies by Hans Selye were pivotal in stress research but raise important ethical concerns.<\/div>\nSelye initially focused on sex hormones in rats, but he incidentally discovered that prolonged exposure to stressors \u2014 such as extreme cold, surgical injury, and excessive muscular exercise \u2014 led to adrenal enlargement, thymus and lymph node shrinkage, and stomach ulceration in the rats. Selye realised that these health issues were part of a set of body reactions that occur over time under stress, regardless of the stressor's nature. He termed this the general adaptation syndrome<\/strong>, a universal response of the body to stress.\n\nIt is important to note that Selye's experiments, while groundbreaking, involved methods that would not meet current ethical standards. The distress and harm inflicted on the rats in his labs raises significant ethical concerns. Additionally, the extrapolation of these findings to human populations should be approached with caution.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"649\"] Figure WB.11. Selye\u2019s general adaptation syndrome.<\/strong> This graph illustrates the three stages of Selye\u2019s general adaptation syndrome: alarm reaction, resistance, and exhaustion. Prolonged stress ultimately results in exhaustion.[\/caption]\n\nSupplement WB.16: Deep Dive - Two examples of Understanding general adaptation syndrome [New Tab]<\/a><\/div>\nIn summary, Selye's general adaptation syndrome model illustrates how our bodies may respond to stress in stages: initially with a burst of energy, then adapting, and finally, potentially breaking down if the stress continues for too long.\nBiological Basis of Stress<\/h1>\nWhat happens inside our bodies when we experience stress? The physiological mechanisms are complex, involving two main systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.\n\nWhen we perceive something as stressful, the sympathetic nervous system quickly triggers arousal. This includes releasing adrenaline from the adrenal glands, which activates our fight-or-flight responses, such as a faster heart rate and increased breathing. Simultaneously, the HPA axis, which operates more slowly, becomes active. The hypothalamus in the brain releases a hormone that prompts the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete various hormones, notably cortisol, which affects almost every organ and provides an energy boost in response to stressors.\n\n[caption id=\"attachment_493\" align=\"aligncenter\" width=\"731\"]
Figure WB.12. Hypothalamic-pituitary-adrenal (HPA) axis.<\/strong> This diagram illustrates the HPA axis, showing how the hypothalamus activates the pituitary gland, which in turn stimulates the adrenal glands to increase cortisol secretion.[\/caption]\n\nIn short bursts, this process can be beneficial, providing extra energy, temporarily improving immune function, and reducing pain sensitivity. However, prolonged or chronic stress, leading to extended cortisol release, can have detrimental effects. High cortisol levels can weaken the immune system and are often found in individuals with depression (Glaser & Kiecolt-Glaser, 2005; Geoffroy, Hertzman, Li, & Power, 2013).\n\nThese physiological reactions to stress prepare us for immediate action but can also increase the risk of illness. Extreme or chronic stress can have profound negative consequences. It contributes to psychological disorders like post-traumatic stress disorder (PTSD) and depression and is linked to physical illnesses. For instance, people affected by the September 11 attacks showed higher rates of heart disease (Jordan, Miller-Archie, Cone, Morabia, & Stellman, 2011). Finnish food industry workers with self-reported stress symptoms were more likely to develop various disorders 11 years later (Salonen, Arola, Nyg\u00e5rd, & Huhtala, 2008). South Korean employees with high work-related stress were more susceptible to the common cold (Park et al., 2011).\n\nHaving explored the immediate physiological responses to stress, we will now examine how these reactions can lead to physical illness and disease. In the following sections, we will delve into the mechanisms through which stress can lead to physical illness and disease.\n\nWatch this video: Sympathetic Nervous System: Crash Course Anatomy & Physiology #14 (11 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=0IDgBlCHVsA\n\n\u201cSympathetic Nervous System: Crash Course Anatomy & Physiology #14\u201d video by CrashCourse is licensed under the Standard YouTube licence.\nRat Park Experiments, Addiction and Environmental Stress<\/h1>\nWatch this video: Addiction and the Rat Park Experiments - Short Version (1.5 minutes)<\/a>\n\nhttps:\/\/www.youtube.com\/watch?v=xNmEboNEnd8\n\n\u201cAddiction and the Rat Park Experiments - Short Version\" video by MinuteVideos Portfolio is licensed under the Standard YouTube licence.<\/span>\n
Supplement WB.17: Deep Dive - The Rat Park Experiments Explained [New Tab]<\/a><\/div>\nSupplement WB.18: Deep Dive - Graphic Narrative Story: Rat Park by Stuart McMillan [New Tab]<\/a><\/div>\nLife Changes as Stressors<\/h1>\nLife changes, whether perceived as positive or negative, can act as significant stressors. The Social Readjustment Rating Scale (SRRS), developed by Holmes and Rahe in 1967, highlights how events like marriage, divorce, job loss, or moving to a new home require an individual to make substantial adjustments, thereby inducing stress. These life changes are assigned \"life change units\" (LCUs) to quantify their potential impact on a person's health. Interestingly, the scale suggests that not only negative events but also positive ones, such as promotions or the birth of a child, can produce stress due to the changes they bring to one's life.\n
Supplement WB.19: Deep Dive - What Stresses Us Out? [New Tab]<\/a><\/div>\n