The neurobiology of suicide and suicidality.

OBJECTIVE: To investigate the current state of knowledge regarding the neurobiology of suicide and suicidality.
METHOD: The literature on the neurobiology of suicidality and suicide was reviewed.
RESULTS: There is clear evidence that the activity of 3 neurobiological systems has a role in the pathophysiology of suicidal behaviour. This includes hyperactivity of the hypothalamo-pituitary-adrenal axis, dysfunction of the serotonergic (5-HTergic) system, and excessive activity of the noradrenergic system. While the first and the last system appear to be involved in the response to stressful events, dysfunction of the serotonergic system is thought to be trait-dependent and associated with disturbances in the regulation of anxiety, impulsivity, and aggression. It can be hypothesized that neurobiological dysfunctions mediate the occurrence of suicidal behaviour through the disturbed modulation of basic neuropsychological functions.
CONCLUSION: Increasing insight into the neurobiological basis of suicidal behaviour suggests that serotonin (5-HT) agonists have an important role in the treatment and prevention of suicidal behaviour. Studies of the efficacy of such drugs have, however, been disappointing. Because suicidal behaviour continues to be a major public health problem, further study is clearly needed, including research on the effect of combined pharmacologic and psychotherapeutic approaches.