"This study is very exciting because it shows that negative emotions affect cognition differently than positive emotions in these kids," said Dr. Mani Pavuluri, associate professor of psychiatry at UIC's Institute for Juvenile Research and the Center for Cognitive Medicine, and lead author of the study.
Using functional magnetic resonance imaging, Pavuluri and her colleagues examined the brain activity of teens while they were performing certain mental tasks. The researchers scanned the brains of 10 unmedicated bipolar patients with normal mood and compared them with 10 healthy subjects of the same age and gender.
The children, aged 12 to 18, were asked to match positive or negative words with colors to determine how stimuli impact different areas of the brain responsible for emotion and cognition.
When shown negative words, compared to neutral words, the bipolar patients showed increased activation in the part of the brain that regulates emotions. When shown positive words, they showed activation in the reward centers of the brain which are often associated with pleasure and addiction.
In healthy subjects, positive and negative words activated the regions of the brain associated with cognitive behavior such as thinking, reasoning and learning.
"We found that the amygdala, the part of the brain that is supposed to react to emotional stimuli, is over-reactive to negative stimuli in children with bipolar disorder," said Pavuluri. "And the part of the brain that controls cognitive behavior is under-reactive."
Results of the study will be presented Oct. 20 at 2 p.m. at a joint meeting of the American Academy of Child and Adolescent Psychiatry and the Canadian Academy of Child and Adolescent Psychiatry in Toronto.
Pavuluri says the findings have direct clinical implications for present and future medication trials and cognitive behavioral therapy used to treat children with bipolar disorder.
Pediatric bipolar disorder, also known as manic depression, is associated with sexual promiscuity, failure in school, addiction and suicide. The disorder is characterized by extreme changes in mood and is often misdiagnosed. Patients may alternate between depression and euphoria, or mania.
Other UIC researchers in the study were Subhash Aryal, Megan O'Connor, Erin Harral, Ellen Herbener, and senior collaborator John Sweeney.
For more information about the pediatric mood disorders clinic at UIC's Institute for Juvenile Research, visit www.psych.uic.edu/pmdc or call (312) 996-7723. For information on research studies or participation, call (312) 413-1710.
UIC ranks among the nation's top 50 universities in federal research funding and is Chicago's largest university with 25,000 students, 12,000 faculty and staff, 15 colleges and the state's major public medical center. A hallmark of the campus is the Great Cities Commitment, through which UIC faculty, students and staff engage with community, corporate, foundation and government partners in hundreds of programs to improve the quality of life in metropolitan areas around the world.