Stress - body - brain
Stress - body and brain
During times of stress, the links between the brain and bodily functions are strong. The brain is sending signals that release hormones, including cortisol and adrenaline. As a result, the heart pumps faster; blood pressure goes up; and blood flow shifts to parts of the body that need it the most (e.g. brain and muscles so we can think fast and fight or run). If the brain is exposed for a prolonged period of time to stressful stimuli, the body does not have a chance to recuperate and the results can be devastating. Research suggests that wide fluctuations or prolonged elevation in glucocorticoid levels have neurotoxic effects. Sudden reductions may play a role in inflammatory brain disease, and normal levels are required to prevent stress-activated or toxin-mediated defence mechanisms from overshooting, causing inflammations such as encephalomyelitis.
By contrast, an excess of circulating glucocorticoids has been noted to be associated with loss of receptors in the hippocampus, which is crucial in learning, memory, and emotion. The removal of the adrenal glands in the treatment of Cushing’s disease has also improved psychiatric symptoms such as depression.
Cortisone reverses the mental symptoms of adrenal insufficiency (Addison’s disease) even when physical signs are absent. Adrenal steroid excess causes syndromes associated with affective disorders such as anxiety, dysphoria, agitation, dyssomnia, and psychotic episodes.