A new study of adolescents and young adults with bipolar disorder has found structural and functional differences in the brains of those with the disorder who have attempted suicide and those who have not. It has been estimated that about half of people who have bipolar disorder make at least one suicide attempt in their lifetime. The differences uncovered in the study could help researchers identify young people who are at the greatest risk.
Although people with bipolar disorder tend to start having suicidal thoughts in adolescence or young adulthood—when parts of the brain involved in emotional processing are still maturing—few studies have examined neural circuitry associated with suicidal behavior in individuals at this age.
In the new study, published January 31 in the American Journal of Psychiatry, researchers led by Hilary P. Blumberg, M.D., used several different types of magnetic resonance imaging (MRI) to study the brains of people with bipolar disorder between the ages of 14 and 25, comparing 26 individuals who had attempted suicide to 42 who had not. Blumberg is a NARSAD 2002 Young Investigator, 2006 Independent Investigator, BBRF Scientific Council member, and 2006 Klerman Prizewinner at Yale University.
The team, which included 2008 and 2012 Young Investigator Fei Wang, Ph.D., and 2016 Young Investigator Jie Liu, Ph.D., found that among those who had attempted suicide, parts of the brain that regulate emotion and impulses were smaller in size and less active than they were in the other study participants. The white matter connecting those brain regions was also diminished in those who had attempted suicide. Abnormalities in these brain regions have also been observed in adults with various psychiatric disorders who have attempted suicide.
Specifically, compared with the non-attempter group, the attempter group showed significant reductions in gray matter volume in the orbitofrontal cortex, hippocampus, and cerebellum; in white matter integrity in the uncinate fasciculus, ventral frontal, and right cerebellum regions; and in amygdala functional connectivity to the left ventral and right rostral prefrontal cortex. In exploratory analyses, among attempters, there was a significant negative correlation between right rostral prefrontal connectivity and suicidal ideation and between left ventral prefrontal connectivity and attempt lethality.
Zeroing in on the neural systems that underlie suicidal behavior is critical for developing new strategies for prevention, the researchers say. Their findings could help researchers develop interventions that aim to prevent suicide by improving the function of these disrupted brain circuits.
Post by Brain & Behavior Research Foundation Staff