This study utilized multimodal neuroimaging techniques to investigate neurobiological mechanisms underlying suicidal behavior in veterans. Results show increased myoinositol in the anterior cingulate cortex and increased white matter connectivity of the posterior cingulate cortex in suicidal veterans. Suicidal female veterans exhibited lower gamma-amino butyric acid (GABA) levels than non-suicidal female veterans, which was not seen in male veterans

Neuroscientists have used brain imaging techniques to learn many things about the brain—how the depressed brain differs from a normal brain, for example, and which parts of the brain are engaged when a person calls up memories. But there have been few studies attempting to find brain characteristics that are associated with suicidal behavior. Thus Deborah Yurgelun-Todd of the University of Utah is now studying a group of Veterans, half of whom have a history of self-directed violence, to search for brain differences between Veterans who have attempted to hurt themselves and those who have not.

Yurgelun-Todd has been doing similar studies for 20 years, using neuroimaging to look for patterns of brain changes that are associated with different patterns of behavior. Depression offers a good example of the sorts of brain changes that can be seen with brain imaging, she says. For examples, when individuals are depressed they have less brain activity than usual in the frontal cortex, the part of the brain that is responsible for, among other things, reward, attention, planning, and motivation. When people are depressed, she notes, their thinking is slowed, and they tend to perform somewhat worse than usual on a number of different tasks. In addition to depression, Yurgelun-Todd has also used brain imaging to study brain changes in individuals with traumatic brain injury.

To look for ways in which the brains of suicidal Veterans are different from the brains of Veterans who are not suicidal, she is recruiting 80 Veterans to undergo a variety of neuroimaging studies and to be assessed for suicide risk. Half of the Veterans will have committed at least one act of self-directed violence, while the other half will have no such history. Yurgelun-Todd will examine a number of aspects of brain structure and function in these 80 Veterans, including the amount of white matter, the volume of various brain regions, the degree of brain connectivity, and the concentration of various chemicals in different parts of the brain—indeed, just about everything that is possible to learn about the brain with neuroimaging. The goal is to find patterns of changes in brain structure or activity that correspond with various suicide-related behaviors, psychological traits, or patterns of thinking.

Assuming that she does find such neuroimaging correlates of suicide risk, there are various ways that these findings may help with reducing suicidal behavior, Yurgelun-Todd says. They could be used, for instance, in diagnosing those at elevated risk of suicide, perhaps even before that risk could be detected using traditional tests. They could be used to look for and monitor brain changes as at-risk individuals go through treatment. They could be used to indicate which types of treatment are likely to be most effective for a given individual. Or, on a more fundamental level, they could be used to provide insights into what is happening in the brain of at-risk individuals that makes them more likely than others to attempt suicide. In short, such neuroimaging holds the promise of providing a new and powerful tool for studying, diagnosing, and directing the treatment of suicidality.