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Welcome to MRC Psycho Big Go. Revision is a child. I missed Henry and the SCO. I spent a lot of time for you too. MRC Psychic for the video. So I started this podcast to help you revise in the goal. Each episode breaks down one healed topic, mapped to the syllabus. This is then followed by five questions to help reinforce your learning. So grab your headphones, turn travel time into revision time, and let's get started. In the previous three episodes, we explored the psychology of conflict and trauma, including Lewin's three types of motivational conflict, the neurobiology and management of PTSD. We established that stress is generated by external events and internal conflicts, but one observation keeps arising. Not everyone who faces the same stressor develops the same outcome. Individual differences in vulnerability and resilience profoundly shape the relationship between stress and illness. One framework for understanding this is the diathesis stress model. The diathesis stress model proposes that psychiatric and physical disorders result from an interaction between a pre-existing vulnerability or diathesis and exposure to stress. The diathesis may be genetic, biological, psychological or social. The stressor acts as a trigger that activates the vulnerability and leads to disorder. This model explains why individuals with similar stress exposures can have very different outcomes. Those with greater diathesis require less stress to reach the threshold for illness. In modern psychology, we often visualize this model using the metaphor of orchids and dandelions. Dandelion individuals have low vulnerability, they can thrive in almost any soil. Orchid individuals possess high biological vulnerability. They wither easily under harsh conditions, but given the right environment, they bloom spectacularly. Remember, the diathesis stress model proposes that illness results from the interaction between a pre-existing vulnerability and a stressor. Vulnerability factors can be grouped into three broad domains. Biological vulnerability includes genetic predisposition to illness, dysregulation of the HPA axis, impaired immune function, and structural brain differences such as reduced hippocampal volume. Psychological vulnerability includes a history of adverse childhood experiences, insecure attachment, and preexisting mental health difficulties. Social vulnerability includes poverty, social isolation, lack of social support, unstable housing, and exposure to chronic discrimination or adversity. Protective factors or invulnerability factors are the mirror image of these vulnerabilities. They include positive social support, secure attachment, adaptive coping styles, a sense of control and purpose, and access to material resources. We will return to these themes in our episode on resilience. Remember, vulnerability factors span biological, psychological, and social domains. Protective factors in each domain buffer against the impact of stress and reduce the risk of illness. One of the most striking demonstrations of the relationship between personality, behavior, and stress-related illness came from the research of Meyer Friedman and Ray Rosenman, two cardiologists working in San Francisco in the nineteen fifties. The story of their discovery is memorable. A furniture upholsterer who had been called to repair the chairs in their waiting room commented that the chairs were worn in an unusual way. The front edges of the seats were worn down rather than the back, and the armrests were clawed and torn from the inside, as though the patients were locked in a constant state of bracing. This observation prompted them to investigate whether a distinctive behavioral pattern might be associated with heart disease. Their subsequent research led to the identification of type A behavior. Type A behavior is characterized by a cluster of traits including time urgency and impatience, competitive and achievement oriented striving, hostility and irritability when frustrated, and a tendency to do multiple things simultaneously, known as polyphasic activity. Type B behavior, by contrast, describes individuals who are more relaxed, less time pressured, less competitive, and more able to engage in leisure without guilt. Remember, type A behavior is characterized by time urgency, competitive striving, hostility and polyphasic activity. Type B behavior is more relaxed and less driven. Friedman and Rosenman tested their hypothesis in the Western Collaborative Group Study, which began in nineteen sixty. They recruited over three thousand healthy men aged thirty nine to fifty nine in California, and assessed their behavior type at baseline using a structured interview. The structured interview was designed not only to capture what participants said, but how they said it. Interviewers would deliberately stutter, stammer, or trail off mid-sentence saying things like the Um Weather in San Francisco is Type B individuals would wait calmly for the interviewer to finish, but type A individuals couldn't help themselves. They would physically lean forward, show micro expressions of irritation, and aggressively finish the sentence for them is foggy, yes we know. These behavioral interruptions were scored as primary markers of type A behavior. After eight and a half years of follow-up, type A men had approximately twice the rate of coronary heart disease compared to type B men, even after controlling for traditional risk factors such as smoking, blood pressure, and cholesterol. The biological mechanism proposed was that chronic activation of the sympathetic nervous system, driven by the hostility and urgency characteristic of type A behavior, leads to repeated surges in adrenaline and cortisol, promoting atherosclerosis and cardiovascular damage over time. Later, research refined the type A concept. Subsequent analysis suggested that hostility was the most cardiotoxic component of the type A constellation. More recently, researchers have described type D personality, standing for distressed personality proposed by Johann Denolle in the nineteen nineties. Type D personality is characterized by two stable traits negative effectivity, a tendency to experience negative emotions such as anxiety, dysphoria and irritability, and social inhibition, a tendency to suppress emotional expression in social situations due to fear of disapproval. Type D personality has been associated with increased risk of cardiac events, poorer recovery after myocardial infarction, and increased rates of depression and anxiety. Its relevance to psychiatry lies in its overlap with internalizing psychopathology and its association with worse mental and physical health outcomes. Remember, type D personality is characterized by negative affectivity and social inhibition. It is associated with worse cardiovascular and psychiatric outcomes. Now, let's test your recall. I will read out five exam style questions. After each one, I will pause for ten seconds so you can attempt them before hearing the answer. Question one. Two siblings both lose their jobs in the same month. One develops a depressive episode, the other appears to cope well. What model accounts for this difference?

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The diathesis of the stress model.

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Question two. What were the main findings of the Western collaborative group study?

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Type A men had approximately twice the rate of coronary heart disease compared to type B men. Question three, a consultant cardiologist is known for his explosive temper with colleagues, frequently interrupts patients mid-sentence, and always arrives early to every meeting. Which component of type A behavior is most predictive of his cardiovascular risk? And why? Hostility, as it is associated with chronic sympathetic activation and repeated cortisol surges that promote atherosclerosis. Question four. What are the two defining traits of type D personality?

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Negative affectivity and social inhibition.

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Question five. Name one biological, one psychological, and one social vulnerability factor for stress-related disorder. For biological HPA, axis dysregulation or genetic predisposition. For psychological, history of adverse childhood experiences or insecure attachment. For social poverty, social isolation or lack of social support. Let's summarize what we have learned today. The diathesis stress model proposes that illness results from the interaction between preexisting vulnerability and stress. Greater diathesis lowers the threshold for disorder. Vulnerability factors span biological, psychological, and social domains. Protective factors in each domain buffer against stress. Friedman and Rosamond identified type A behavior. The Western Collaborative Group study found type A men had twice the coronary heart disease rate of type B men. Hostility is the most cardiotoxic component. Type D personality, characterized by negative affectivity and social inhibition, is associated with worse cardiovascular and psychiatric outcomes. In our next episode, we explore how people appraise and cope with stress. We will cover Lazarus and Falkmann's transactional model of stress and coping, including primary and secondary appraisal, and the distinction between problem-focused and emotion-focused coping strategies. I hope this episode helped to move your provision forward. If you have any questions or just want to continue the discussion, you can find me on LinkedIn MRT Type on the Go.