Project Summary Environmental cues and signals are fundamental in the regulation of behavioral decision making. For decades this aspect of social behavior has been a major focus of environmental psychology and neuropsychiatry research. Yet the complexity of the mammalian nervous system and the lack of experimental traction in humans has limited a mechanistic understanding of how environmental influences shape sensory processing and social behavior. The goal of this proposal is to take advantage of the comparatively simple nervous system of Drosophila to identify the functional neural basis of environmental control over social behaviors, which has the potential to inform our understanding of devastating neuropsychiatric conditions characterized by the failure to appropriately process social and other environmental cues. In my experimental approach I leverage the power of striking natural variation in the environmental control over mating behaviors across species in a comparative framework and combine it with the unparalleled neurogenetic toolkit of Drosophila to isolate causal neural circuit mechanisms through which environmental cues control behavior. In the mentored phase of this award, I will elucidate the functional integration of food odors with male courtship circuits (Aim 1) and characterize how visual cues emitted by the social group regulate female copulation decisions (Aim 2) using a combination of in vivo functional brain imaging in a multimodal virtual reality system, optogenetics, and neuroanatomy approaches across two species with divergent behaviors. The comparison of alternative circuit architectures underlying behavioral differences will allow me to isolate the circuit motifs and dynamics that control the functional integration of these environmental cues with central mating circuits. For the independent phase of the award, I will transfer the skills and techniques acquired during the training phase to develop a new model for comparative neuroscience. This will allow me to elucidate the neuronal functional principles underlying bacterial manipulations of the nervous system that alter the perception of environmental signals and manipulate mating behavior of infected individuals in the bacteria’s favor (Aim 3). The proposed professional development plan under the continued mentorship of Dr. Vanessa Ruta complements my training in evolutionary biology, chemical ecology and systems neuroscience with the background and techniques necessary to complete the proposed research and shed new light on the functional mechanisms of environmental control over social behavior. To achieve these goals, I will take advantage of the extensive resources of the Rockefeller University and my advisory committee, that will provide expert guidance in key aspects of the project and career development. Together this will set me up optimally to successfully transition to an independent position and start my own lab exploring the mechanisms underlying the sens...