Humans and other animals use odors to guide a variety of behaviors critical for survival. However, the neural mechanisms by which odor molecules in the environment are processed within the brain to yield perception are not resolved. Surprisingly, even a basic description of what types of odors are represented by one major olfactory structure, the olfactory tubercle (OT), is not available. Elucidating the role of the OT in olfaction will help clarify the process of olfactory perception. Therefore, the present proposal describes an experimental strategy aimed to elucidate the contributions of the OT to olfactory processing by combining neurophysiological, behavioral and computational methods in mice. It is predicted that OT neurons will display a unique representation and responsivity to odors in comparison to another primary olfactory cortex (the piriform cortex). Further, it is predicted that OT neuronal activity in response to odors will dramatically differ based upon behavioral state, including anticipation and reward-conditioning, thus positioning the OT as a link between perception and behaviorally-relevant processes. Together, these findings will enhance our understanding of information processing and, more specifically, how olfactory perception is formed within the brain. Broader impacts resulting from the proposed activity include the training of high school, undergraduate, and graduate students in core aspects of neurophysiology and behavioral neuroscience. The project will extend special effort to involve women and under-represented minorities. Furthermore, it will provide a mechanism to bridge ties between local (Cuyahoga county) high schools and colleges (Cleveland State U. and John Carroll U.) and the Case Western Reserve University (CWRU) by allowing students exposure to scientific training through aspects of this proposal.
A major question of wide importance is how our brains allow for us to interact with the world around us. The mammalian olfactory system is an ideal model whereby to study sensory processing. Olfactory cortical areas, including the piriform cortex (PCX) and olfactory tubercle (OT), receive odor information from second order neurons in the olfactory bulb (OB) and are thought to play a critical role in odor perception. The objectives outlined of this proposal were to elucidate the role of an especially understudied olfactory cortical area, the OT, to the processing of odor information. We employed a variety of physiological and behavioral methods to uncover fundamental features whereby the OT transforms odor information in manners possibly advantageous for perception. The results of the experiments have extending basic anatomical data on the OT into an understanding of its contribution to odor processing and perception. The project has resulted in numerous publications and presentations at both regional and international conferences by laboratory members. Further, over a dozen Cleveland-area students, ranging from high school, undergraduate, to graduate level, received training in core concepts of biology, neuroscience, and biomedical research during the course of the project. The laboratory also engaged in local community scientific outreach activities, including scientific presentations at local high schools and in-lab training of a local urban high school teacher to aid in the development of lesson plans.
