Grant: Operating Grant

Deficits in decision-making behavior are a major aspect of many brain disorders, including diseases such as Parkinson's and maladaptive conditions such as addiction. Understanding the neural bases of decisions is therefore critical to developing more effective therapies that act at the sources of the deficit without disturbing other brain functions. Most research investigates the neural mechanisms of decision-making by studying how we make choices using static information about explicit predictable outcomes, such as choosing between two jars of peanut butter in a grocery store. However, during the brain's evolution animal behavior was dominated by decisions about actions in a constantly changing world, such as choosing which way to run away from a predator. Such "embodied decisions" still dominate our lives, whether we're playing a sport, walking through a crowd, or maneuvering through a store to get to the peanut butter aisle. Because these kinds of decisions have been so central in evolution, their study is needed to provide insights into mechanisms of decision-making at the neural level. This project aims to understand how the brain makes decisions in situations that are changing over time, and how a commitment is made to an action choice. It involves recording neural activity in the cerebral cortex and subcortical regions of monkeys trained to perform reaching tasks in different changing and ambiguous situations. It tests specific predictions of a general hypothesis that during natural behavior, the brain continuously specifies multiple potential actions currently available in the environment while at the same time collecting information for selecting one of them for execution at a given moment. Because the hypothesis proposes specific functional roles for specific brain regions, it is expected to help explain the deficits associated with damage to these regions and to suggest how these deficits may be alleviated.