Electrophysiological and Computational studies on action monitoring

Brown University, Providence RI

Investigators

Abstract

How humans regulate their behaviors is a fundamental question. With funding from the National Science Foundation, Dr. Michael Frank of Brown University is investigating interactions between different brain regions involved in how people monitor, learn, and control their actions. This research project focuses on how humans accomplish restrained control over behavior when confronted with difficult decisions. Theoretical models and empirical results suggest that the prefrontal cortex and the basal ganglia interact during these motivated behaviors, and that the neurochemical dopamine plays a central role in both the prefrontal cortex and basal ganglia brain regions. Using electroencephalography (EEG), the investigators are measuring participants' brain waves associated with prefrontal cortex activity, while they perform computerized cognitive tasks that assess learning and decision making in difficult circumstances. The brain wave activity is expected to predict participants' cognitive performance on these tasks. Critically, this brain-behavior relationship is predicted to differ as a function of genetic variants in dopamine function in both the prefrontal cortex and basal ganglia. In another experiment, researchers are directly manipulating dopamine pharmacologically in order to determine how these brain and behavior relationships are causally altered by dopamine levels. In all of their studies, the investigators use detailed mathematical models guided by contemporary theory to isolate specific brain-behavior relationships. It is theorized that both genetic variants and pharmacological manipulations affect the way that the brain monitors, learns, and controls actions. The brain wave measures are allowing the research team to define how neurochemicals modulate the processes of large neural systems. This research has the goal to substantially advance our understanding of how humans are able to regulate their behaviors as a function of motivation and cognitive control. Scientists widely appreciate that there are large individual differences in these types of motivated behaviors, but only recently have they begun to understand some of the factors governing these differences. By combining multiple research approaches, this project is posed to reveal the ways in which genetic and neurochemical factors alter activity in brain areas that are critically involved in such behaviors. The project also has the potential to identify mechanisms that disrupt brain circuitry and lead to disorders in motivated behavior and cognitive control, including addiction and obsessive compulsive disorder among others.