**This seminar will take place virtually via Zoom. A link to view will be posted closer to the seminar date.**
This month's speakers:
Robert Yang, PhD, (Abbott lab): "Machine evolving the olfactory system"
Flies and mice are separated by 600 million years of evolution yet they have evolved olfactory systems that share many anatomic and functional features. The similarity of the olfactory systems in evolutionarily distant organisms may reflect a common drive to enable rapid learning of novel olfactory associations and to elicit innate behavioral responses to salient odors. We asked whether networks constructed by the machine learning to perform olfactory tasks converge on the same structural organization as these natural olfactory systems. Artificial networks trained to classify odor identity recapitulate structural principles inherent in the olfactory system, including input units driven by a single receptor type, the convergence of similarly responding input units onto 'glomeruli', and sparse unstructured connectivity to a large third-layer representation.
Wataru Yamamoto, PhD (Yuste lab): "Studying Neuronal Mechanisms of Decision-Making and Learning in Hydra vulgaris"
Sensory cues (e.g. food or threat) can cause animals to quickly switch behaviors based on simple cost- benefit computation that is crucial for survival. However, the underlying neural-circuit mechanisms responsible for sensorimotor integration have remained largely unclear. To address this, we use a cnidarian Hydra vulgaris for their simple nervous systems, called a nerve net, to image entire neuronal activity during behavior. We show that the activity of neuronal circuit with previously unclear function can trigger locomotion, a series of motor behavior. Furthermore, Hydra habituates to chemical stimuli that induce feeding, which involves disinhibition of two neuronal circuits. These findings suggest the characterization of neuronal activity during behavior can provide insights into learning and decision-making in this cnidarian.