Stress damage due to early / prolonged stress
Stressors activate the various stress systems in humans, which act in parallel. The most important of these are the autonomic nervous system (sympathetic/parasympathetic nervous system), which is activated quickly by electrical nerve impulses, and the HPA axis, which is activated slowly by hormones. The HPA axis releases stress hormones in a relay, starting with CRH and vasopressin, followed by ACTH and ending with cortisol. At higher levels, these trigger stress symptoms (which is healthy up to this point). However, they have a neurotoxic effect if they are released over a long period of time.1234 If the levels are too low, the stress symptoms and stress reactions are not formed sufficiently and the HPA axis cannot be shut down properly if the cortisol release is too low.
⇒ The HPA axis / stress regulation axis
The neuroplastic effect of prolonged stress was described as an allostatic concept as early as 1988.56
Prolonged stress leads to an allostatic overload7 (acute pathological consequences of allostatic reactions), which causes changes in the following brain regions, among others, which in turn changes behavior and physiological reactions:
- Hippocampus (volume reduction)
- Cognitive impairments
- Depression
- Impairment of self-esteem
- Amygdala
- PFC
Stress exposure has very different effects depending on the age of the individual.8910
Different types of stressors and different types of exposure to stressors have different effects:
- Stress by age at exposure - early childhood stress
- Stress by duration: Long-lasting, chronic stress
- Stress by type of stressor
- Stress effect by gender
- Diagnosis of stress system damage
- Resilience, increased sensitivity, genetic disposition and maternal care
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