Final answer:
The diathesis-stress hypothesis posits that mental illnesses are a result of the interaction between genetic vulnerability and environmental stressors. Stressful life events can activate an individual's predisposition to mental disorders, while chronic stress can overwhelm coping mechanisms and lead to various psychological conditions.
Step-by-step explanation:
Diathesis-Stress Hypothesis
The diathesis-stress hypothesis is a psychological theory that explains the causes of mental illnesses. It proposes that mental disorders develop due to a combination of genetic vulnerability (diathesis) and environmental stressors. According to this hypothesis, individuals have certain predispositions for mental illnesses, which may remain dormant until triggered by stressful life events or chronic stress. Stress-induced activation of physiological systems, as described by Robert Sapolsky, illustrates how prolonged stress without adequate recovery can lead to mental stress contributing to various disorders, including post-traumatic stress disorder and major depressive disorder. The hypothesis emphasizes the interaction between a person's biological characteristics and their environmental experiences, indicating that no single factor is solely responsible for the development of a mental disorder.
For example, an individual may have a genetic tendency towards depression but will not necessarily develop the condition unless they experience significant life stressors. Likewise, even without a strong genetic predisposition, high levels of stress may still lead to psychological conditions by overwhelming an individual's coping mechanisms. This view aligns with research findings on the substantial impact of stress on psychological and physical health, underscoring the importance of considering both innate vulnerabilities and environmental pressures in the onset and progression of mental illnesses.