Chronic stress

Chronic stress is the response to emotional pressure suffered for a prolonged period over which an individual perceives he or she has no control. It involves an endocrine system response in which occurs a release of corticosteroids. While the immediate effects of stress hormones are beneficial in a particular situation, long-term exposure to stress creates a high level of these hormones that remains constant. This may lead to high blood pressure (and subsequently heart disease), damage to muscle tissue, inhibition of growth, suppression of the immune system, and damage to mental health.

Physiology

Animals exposed to distressing events over which they have no control respond by releasing corticosteroids. The sympathetic branch of the nervous system is activated, also releasing epinephrine and norepinephrine. These, if prolonged, lead to structural changes in the brain. Changes happen to neurons and their synapses in the hippocampus and medial prefrontal cortex. These produce impairments in working memory and spatial memory, as well as increased aggression.