Neurobiology of Stress and Resilience
The stress response is a physiological and psychological reaction that is activated when an individual is confronted by a challenging situation. [Seyle 1973]
When confronted by a stressful life event such as trauma, tragedy, or a perceived threat, there are structural and functional alterations to the brain [McEwen et al 2015]:
- Remodelling of the neural architecture is indicative of successful adaptation and neuronal plasticity through a physiological response known as allostasis.
- Allostatic overload can be caused by multiple and/or chronic stressors, which are known risk factors for psychiatric disorders such as depression and anxiety.
- However, most individuals display resilience to adversity, whereby the negative impact of stressful events is reduced.
- Stress resilience is designed to maintain allostasis and is an ordinarily common outcome that allows individuals to withstand, or even thrive, despite these stressful circumstances.
- In contrast, there is a significant minority that are psychologically vulnerable to the negative consequences of trauma and thus develop chronic debilitating psychological symptoms.