Tracing the Neural Circuitry of Rewarding Brain Stimulation

University Of Wisconsin-Whitewater, Whitewater WI

Investigators

Abstract

This work will begin to map brain circuits that carry the reward signal believed to be generated when animals successfully meet motivational goals, such as finding food when hungry. Such a signal is thought to inform the animal that its current behavior is important to its survival, and to reinforce the continuation of that behavior. Electrical stimulation of the medial forebrain bundle has long been believed to create a potent and non-satiating version of the reward signal, yet the circuitry traversed by this signal outside of this major axon pathway is still unknown. Brain areas critical to carrying the signal will be revealed by psychophysically tracking changes in the reward magnitude of medial forebrain bundle stimulation when target areas distant from the bundle are temporarily anesthetized. Once reward-relevant targets are identified, the anatomical relationship of these targets to the stimulation sites will be explored electrophysiologically. The stimulation-induced neural activity wilkl be followed to those areas to see whether the neural signals have conduction properties known to characterize the putative reward signal, and whether the target areas are directly or indirectly (i.e., transynaptically) linked to the medial forebrain bundle. This project will increase our understanding of brain circuits involved in reward, with a long term goal of understanding their role in consumptive and other motivated behaviors.