Stephen Cowen

I am interested in the question of how the activities of ensembles of neurons drive our capacity to decide, remember, and navigate. In particular, I am interested in the role of the prefrontal cortex in cost-benefit decision making and in the role of the hippocampus in navigation and memory consolidation. I investigate these topics through large-scale extracellular recording of the activities of networks of neurons and dopamine release in rats as the animals perform decision-making and navigation behaviors. A number of interesting observations have emerged from these experiments. For example, we found that the neurons believed to be critical for working memory also were exquisitely sensitive to small body movements, suggesting a link between working memory systems in the brain and physical movement. This observation that has since motivated the development of novel tools for the analysis and measurement of movement. Our investigation of cost-benefit decision making has revealed that neurons in the anterior cingulate cortex, a region within the frontal cortex, may also be important for the capacity to persevere through physically strenuous sequences of movements (e.g. lifting weights or finishing a marathon) as these neurons respond to specific actions and the effort that must be maintained over time to acquire a goal. Finally, our work in spatial navigation indicates that neurons in the hippocampus, a region that is a critical component of the brain’s navigation system, can rapidly switch between visual and egocentric (body centered) reference frames when the location of a goal demands such switching. Our ultimate goal is to connect our investigations of the frontal cortex and hippocampus in order to determine how communication between these regions guides decision making and memory formation.