The slower neuroendocrine response depends upon the HPA axis and is important for the long-term effects of the stress response as well as various other bodily functions. The stress response is a non-specific physiological reaction to any event (stressor) that takes an organism out of homeostatic range.

The stress response follows an inverted-U pattern: too little or too much stress is deleterious to behavioral performance but there is an optimal level that is beneficial. The stress response depends on multiple interconnected systems working on different timescales.

stress response — a non-specific physiological reaction to any event (stressor) that takes an organism out of homeostatic range. HPA axis and — important for the long-term effects of the stress response as well as various other bodily functions. fast neural response — mediated by the SNS via the sympatho-neural system and sympatho-adrenomedullary system.