LIN Seminar: “Cortical circuits for predictive processing” by Jordan Hamm (Georgia State University)

Please join us at 4pm on March 2, 2023 for a LIN Seminar featuring Dr. Jordan Hamm (Georgia State University)

Hamm Lab

Host: Angie Salles

Abstract: Brain responses to stimuli are not static over time but are dynamically modulated by the context of concurrent and preceding stimuli. This supports the rapid detection of changes in the environment which may be key for flexible behavior and ultimately survival. In the visual system, as early as primary visual cortex (V1), neural activity is strongly modulated by context, showing suppressed responses to stimuli that are redundant or otherwise predictable but augmented responses to stimuli that deviate from perceived regularities or are otherwise unexpected. The former is termed “response suppression”; the latter , “deviance detection.” Critically, visual deviance detection, and its EEG biomarker mismatch negativity, is diminished in people with schizophrenia, suggesting altered predictive processing in cortical systems which could underlie core perceptual and cognitive features of the disease.

My work aims to uncover the cells and circuits which support predictive processing in the mouse visual system. Ongoing projects in my lab involve 1) a deep dive into the dynamic interactions among cortical feed-back circuits and local cortical interneurons during predictive processing paradigms, 2) a study of how these top-down feed-back circuits develop across adolescence, and 3) an interrogation into microglia-neuron interactions and how they shape this circuit development. I highlight key sex-differences, a role of vasoactive intestinal peptide-expressing interneurons (VIPs) in V1 cortex in mediating feed-back modulation, and the impact of a schizophrenia-relevant genetic variant in the Kalrn gene on the development of cortical circuits for predictive processing.