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Date Submitted

Spring 4-17-2015

Research Mentor and Department

Dr. Michael Bruchas

Restricted/Unrestricted

Dissertation/Thesis

Abstract

The neural circuitry underlying mammalian reward behaviors comprises several distinct nuclei throughout the brain. Previous research has indicated that inhibiting the infra-limbic area of the frontal cortex is rewarding to the animal, while activating the central amygdala during reward presentation increases future preference for that reward. Using viral vector-mediated, cell-type specific viral fluorescence tracing in transgenic mice, we identified a GABAergic projection originating in the central amygdala (CeA) that terminates in the infra-limbic area of the frontal cortex. Follow-up experiments to optogenetically activate this circuit in awake, behaving animals produced reward-like behaviors. We hypothesize that activity in these cells inhibits the infra-limbic cortex, and are in the process of in vivo electrophysiological recordings to support this claim. This long-range GABAergic interaction between amygdala and frontal cortex adds a new dimension to the complex regulation of stress- and reward-related behaviors and provides a potential mechanism for the emotional regulation of cognition.