Realizations Inc

Q. Do you know of any studies about the brain and suicide?

A. You may want to obtain a reprint of an article that was published in the February 2003 issue of Scientific American. Reading it strengthened my own belief that changes had to have occurred in the brain in order for suicidal behaviors to be exhibited. According to the article, anatomical and chemical changes occur in two brain regions in people who die by suicide: the orbital prefrontal cortex that lies just above the eyes, and the dorsal raphe nucleus of the brain stem that contains serotonin-producing neurons. The alterations are evidence of a reduced ability to make and use serotonin, a key neurotransmitter known to be lacking in the brains of impulsive people and in those suffering from depression. In suicide victims, the dorsal raphe nucleus sends less than normal amounts of serotonin to the orbital prefrontal cortex.

At a conference of the American College of Neuropsychopharmacology in 2001, Victoria Arango (New York State Psychiatric Institute, affiliated with Columbia-Presbyterian Medical Center) reported that the brains of people who were depressed and died by suicide contained fewer neurons in the orbital prefrontal cortex, that patch of brain just above each eye. What is more, in suicide brains, that area had one-third the number of presynaptic serotonin transporters as compared to brains in the control group, but approximately 30% more postsynaptic serotonin receptors.

Study results have suggested that the brains of people who commit suicide are trying to make the most of every molecule of serotonin they have, by increasing the molecular equipment for sensing the neurotransmitter, while decreasing the number of transporters that absorb it back again. “We believe there is a deficiency in the serotonergic system in people who commit suicide,” Arango concluded. “They can be so sick Prozac can’t help them.” In other words, inhibiting the reuptake of serotonin isn’t always enough to prevent suicide. (Ezzell, Carol. Why? The Neuroscience of Suicide, February 2003, pages 45-51. Scientific American Inc. NY. Web site: www.sciam.com)