Bita Moghaddam: The neural representation of reward and punishment

Bita Moghaddam, Ph.D.

The ability to weigh the risk of punishment relative to the risk of reward is critical to our ability to make decisions.

New research by Bita Moghaddam, Ph.D., provides fresh insight into how the brain processes reward and punishment. Little has been known about the neural representation of punishment risk during reward-seeking behavior. For people to make the best decisions, our brains need to appropriately represent the punishment that lurks during reward-seeking actions. An exaggerated neural representation of risk may lead to anxiety disorders while deficits in this representation may lead to impulsive behavior and addictive disorders.

Moghaddam, Ruth Matarazzo Professor and chair of behavioral neuroscience at the OHSU School of Medicine, and co-author Junchol Park, Ph.D., at the University of Pittsburgh, modeled the neural representation of punishment risk during reward-seeking behavior using a rodent model.

The team designed and validated a task that allowed them to assess reward-guided actions in the absence or presence of punishment risk. The findings, published in the journal eLife, demonstrated sharp distinctions in the level of coordination between a spike in dopamine neurons and activity within the prefrontal cortex, the portion of the brain that regulates complex cognitive functioning.

When there was no risk of punishment, the research team found close coordination between activity in the prefrontal cortex and dopamine levels. When there was a small risk of punishment, there was a marked difference. They found that coordination between the prefrontal cortex and dopamine levels collapsed. That suggests the brain encodes an ingrained assessment of risk in normal circumstances.

The study suggests new avenues of research that could involve functional magnetic resonance imaging of people given risk-reward tasks such as gambling.

Read more about the research at OHSU News.

The study was supported by the National Institute of Mental Health of the National Institutes of Health (grant R56MH084906).