Neurobiology and Behavior Seminar
Tuesday, February 6th, 2018
11 AM, Dale Melbourne Herklotz Conference Center, Center for Neurobiology of Learning and Memory (Building 506 on the campus map)
Gina Turrigiano, PhD
“Self-Tuning Neurons and Firing Rate Homeostasis”
Neocortical networks must generate and maintain stable activity patterns despite perturbations induced by learning and experience- dependent plasticity. There is abundant theoretical and experimental evidence that network stability is achieved through homeostatic plasticity mechanisms that adjust synaptic and neuronal properties to stabilize some measure of average activity, and this process has been extensively studied in primary visual cortex (V1), where chronic visual deprivation induces an initial drop in activity and ensemble average firing rates (FRs), but over time activity is restored to baseline despite continued deprivation. Here I discuss recent work from the lab in which we followed this FR homeostasis in individual V1 neurons in freely behaving animals during a prolonged visual deprivation/eye-reopening paradigm. We find that – when FRs are perturbed by manipulating sensory experience – over time they return precisely to a cell-autonomous set-point. Finally, we find that homeostatic plasticity is perturbed in a mouse model of Autism spectrum disorder, and this results in a breakdown of FRH within V1. These data suggest that loss of homeostatic plasticity is one primary cause of excitation/inhibition imbalances and microcircuit disfunction in ASD models.