Stress damage due to early / prolonged stress
Stressors activate the various stress systems of the human being, which act in parallel. The most important of these are the autonomic nervous system (sympathetic/parasympathetic), which is triggered quickly by electrical nerve impulses, and the HPA axis, which is triggered slowly by chemical hormones. The HPA axis secretes stress hormones in a relay, starting with CRH and vasopressin, followed by ACTH and ending with cortisol. These are stress symptom triggering in at higher levels (which is healthy up to this point). However, if they are released for a long time, they have a neurotoxic effect.1234 If the levels are too low, the stress symptoms and reactions are not formed sufficiently and the HPA axis cannot be shut down cleanly at the end 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 allostatic overload7 (acute pathological consequences of allostatic reactions), which causes changes in the following brain regions, among others, which in turn alters behavior and physiological responses:
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Hippocampus (volume reduction)
- Cognitive impairments
- Depression
- Self-esteem impairment
- Amygdala
- PFC
Stress levels have very different effects depending on the age of the individual.8910
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