The Witten lab: Circuit-level analysis of reward and motivation
How we respond to stimuli in our environment is not static, but is instead fundamentally shaped by our experiences, both positive and negative. For example, if a stimulus has been associated with a rewarding event, it draws our attention, accesses our memory systems, and motivates our behavior. Although neural correlates of these phenomena have been identified in many brain regions, we only now have the tools to begin to understand how neural circuits perform the computations that underlie reward learning and decision making. By integrating a wide range of technical approaches – optogenetics, rodent behavior, in vivo and in vitro electrophysiology, imaging, molecular, and computational approaches – our lab is starting to provide new insights into the circuit-level mechanisms underlying these fundamental processes. Our long-term goal is to describe how individual neural circuit elements map onto the computational algorithms employed by the brain to motivate behavior. Currently our main focus is on characterizing the unique role of neuromodulators, like dopamine and acetylcholine, in encoding reward and motivation, altering circuit activity, and ultimately influencing perceptions and decisions.
The neural circuits underlying reward and motivation play such a fundamental role in supporting normal behavior that their dysfunction results in debilitating neuropsychiatric diseases. In particular, addiction involves the “hijacking” of the natural reward circuitry by drugs of abuse. Thus, we also study the circuit-level mechanisms underlying addiction with the long term goal of identifying new therapeutic avenues to alleviate the condition.