In adolescents with bipolar disorder, key areas of the brain that help regulate emotions develop differently, a new study by Yale School of Medicine researchers shows.
In brain areas that regulate emotions, adolescents with bipolar disorder lose larger-than-anticipated volumes of gray matter, or neurons, and show no increase in white matter connections, which is a hallmark of normal adolescent brain development, according to the imaging study published May 29 in the journal Biological Psychiatry.
The differences were noted in the prefrontal cortex and insula in the magnetic resonance imaging scans — repeated over a two-year period — of 37 adolescents with bipolar disorder when compared to the scans of 35 adolescents without the disorder.
“In adolescence, the brain is very plastic so the hope is that one day we can develop interventions to prevent the development of bipolar disorder,” said senior author Dr. Hilary Blumberg, professor of psychiatry, diagnostic radiology, and in the Yale Child Study Center. She is also the newly appointed John and Hope Furth Professor of Psychiatric Neuroscience.
Bipolar disorder often first appears in adolescence and is marked by severe shifts in mood, energy, and activity levels. Individuals with bipolar disorder can have trouble controlling impulses and have a high risk of suicide and substance abuse.
While adolescents tend to lose gray matter in normal development, the study showed that adolescents with bipolar disorder lose more. Moreover, the study demonstrated that they add fewer white matter connections that typically characterize development well into adulthood. These changes suggest that brain circuits that regulate emotions develop differently in adolescents with bipolar disorder.
Other authors are Pablo Najt (now at the National University of Ireland, Galway), Fei Wang, Linda Spencer, Jennifer A.Y. Johnston, Elizabeth T. Cox Lippard, Brian P. Pittman, Cheryl Lacadie, Lawrence H. Staib and Xenophon Papademetris.
Funding: The research was funded by: the National Institutes of Health (National Institute of Mental Health and National Institute for Drug Abuse), International Bipolar Foundation, Brain and Behavior Research Foundation, American Foundation for the Prevention of Suicide, Klingenstein Foundation, Women’s Health Research at Yale, the Attias Family Foundation, and The John and Hope Furth endowment.
Source: Bill Hathaway – Yale
Image Credit: The image is credited to Blumberg lab and Biological Psychiatry
Original Research: Abstract for “Anterior Cortical Development During Adolescence in Bipolar Disorder” by Pablo Najt, Fei Wang, Linda Spencer, Jennifer A.Y. Johnston, Elizabeth T. Cox Lippard, Brian P. Pittman, Cheryl Lacadie, Lawrence H. Staib, Xenophon Papademetris, and Hilary P. Blumberg in Biological Psychiatry. Published online April 6 2015 doi:10.1016/j.biopsych.2015.03.026
Anterior Cortical Development During Adolescence in Bipolar Disorder
Increasing evidence supports a neurodevelopmental model for bipolar disorder (BD), with adolescence as a critical period in its development. Developmental abnormalities of anterior paralimbic and heteromodal frontal cortices, key structures in emotional regulation processes and central in BD, are implicated. However, few longitudinal studies have been conducted, limiting understanding of trajectory alterations in BD. In this study, we performed longitudinal neuroimaging of adolescents with and without BD and assessed volume changes over time, including changes in tissue overall and within gray and white matter. Larger decreases over time in anterior cortical volumes in the adolescents with BD were hypothesized. Gray matter decreases and white matter increases are typically observed during adolescence in anterior cortices. It was hypothesized that volume decreases over time in BD would reflect alterations in those processes, showing larger gray matter contraction and decreased white matter expansion.
Two high-resolution magnetic resonance imaging scans were obtained approximately 2 years apart for 35 adolescents with bipolar I disorder (BDI) and 37 healthy adolescents. Differences over time between groups were investigated for volume overall and specifically for gray and white matter.
Relative to healthy adolescents, adolescents with BDI showed greater volume contraction over time in a region including insula and orbitofrontal, rostral, and dorsolateral prefrontal cortices (p < .05, corrected), including greater gray matter contraction and decreased white matter expansion over time, in the BD compared with the healthy group. Conclusions
The findings support neurodevelopmental abnormalities during adolescence in BDI in anterior cortices, including altered developmental trajectories of anterior gray and white matter.
“Anterior Cortical Development During Adolescence in Bipolar Disorder” by Pablo Najt, Fei Wang, Linda Spencer, Jennifer A.Y. Johnston, Elizabeth T. Cox Lippard, Brian P. Pittman, Cheryl Lacadie, Lawrence H. Staib, Xenophon Papademetris, and Hilary P. Blumberg in Biological Psychiatry. Published online April 6 2015 doi:10.1016/j.biopsych.2015.03.026