Some assessments of the amygdala role in suprahypothalamic neuroendocrine regulation: a minireview

The amygdala is a complex structure playing primary role in the processing and memorizing of emotional reactions. The amygdalae send impulses to the hypothalamus for activation of the sympathetic nervous system, to the reticular nucleus for increasing reflexes, to the nuclei of the trigeminal nerve and facial nerve for facial expressions of fear, and to the ventral tegmental area, locus coeruleus, and laterodorsal tegmental nucleus for activation of dopamine, norepinephrine and epinephrine release. The amygdala plays a key role in what has been called the "general-purpose defense response control network" and reacts in response to unpleasant sights, sensations, or smells. Anger, avoidance, and defensiveness are emotions activated largely by the amygdale. The amygdala is responsible for activating ancestral signs of distress such as "tense-mouth" and defensive postures such as crouching. Poor functioning of amygdala has also been associated with anxiety, autism, depression, narcolepsy, post-traumatic stress disorder, phobias, frontotemporal dementia, and schizophrenia. Impairment of emotional event memory in patients with Alzheimer's disease also correlates with the intensity of amygdalar damage. All these events speak out for the importance to preserve the normal function of the amygdala which can only be achieved by constant deepening of our knowledge about this unique structure.