The goal of Dr. Wilson's research is to understand neural mechanisms of associative learning. Specifically, the proposed research will investigate the neural substrates of postnatal olfactory learning in newborn vertebrates. This early learning is associated with specific changes in neural structure and function in the olfactory bulb, the first central relay for olfactory information processing. Dr. Wilson's previous work has demonstrated the output neurons in the olfactory bulb, mitral/tufted cells, modify their response patterns to odors learned during the early postnatal period. Furthermore, Dr. Wilson has found that mitral/tufted cells receive convergent information about both odor stimuli and reward stimuli. Importantly, both the behavioral and neural consequences of early learning are morepinephrine dependent, as is at least one component of mitral/tufted cell response to reward. The proposed experiments will examine how mitral/tufted cells are modified during olfactory associative learning and uses a combination of neurophysiological and neuropharmacological techniques to further explore the neural substrates of the descending reward input to the olfactory bulb. Based on his preliminary data, a specific circuit is proposed for convergence of odor and reward information in the bulb involving the primary olfactory nerve and norepinephrine centrifugal inputs to the bulb. Norepinephrine agonists and antagonists will be infused into the olfactory bulb during odor-reward associative conditioning. Response patterns of mitral/tufted cells to the conditioned odor will be examined over the course of the training. The results will provide important information regarding the neural pathways and pharmacology involved in a critical form of learning expressed soon after birth in many animals including humans.***//
