An area of the brain that is responsible for seeking rewards is more strongly activated in people with bipolar disorder, which may explain why those with the condition engage in risky behavior.
Wael El-Deredy, PhD, Manchester University, UK, and colleagues enrolled 40 people with bipolar disorder. Half had bipolar disorder but were not taking antipsychotics, while the other half were healthy controls. The participants were then asked to play a game of roulette and their brain activity was measure with a functional magnetic resonance imaging (fMRI).
In those with bipolar disorder, the fMRIs showed that the nucleus accumbens, known as the brain’s pleasure center, was more strongly activated compared to those without the disorder, the researchers reported in the journal Brain.
In addition, the brain’s prefrontal cortex, which plays a role in helping to coordinate decisions, was found to guide healthy subjects to safer gambles, while in bipolar subjects, it led them to make more risky gambles.
“The greater buzz that people with bipolar disorder get from reward is a double-edged sword,” El-Deredy, PsychCentral reported. “On the one hand, it helps people strive toward their goals and ambitions, which may contribute to the success enjoyed by many people with this diagnosis.
"However, it comes at a cost: these same people may be swayed more by immediate rewards when making decisions and less by the long-term consequences of these actions.”
Researchers are beginning to discover some of the reasons why bipolar disorder can cause people to engage in risky behavior. The condition involves fluctuating depression and mania.
In the manic stage, the patient often feels intense excitement and irritability, which can trigger unpredictable risky behavior. Work, family, and social life all can be impaired by this risk-taking.
Professor Wael El-Deredy of Manchester University, UK, and colleagues investigated the neuroscience behind this risky behavior. They engaged 20 individuals with bipolar disorder but not taking antipsychotic medication and 20 without bipolar disorder.