Intrinsic plasticity and engram formation in neural circuits
Christian Hansel, PhD
Professor, Departmeent of Neurobiology, The University of Chicago, Chicago, IL
Host: Lu Chen
Synaptic plasticity (e.g. long-term potentiation; LTP) is considered the cellular correlate of learning. Recent optogenetic studies on memory engram formation assign a critical role in learning to suprathreshold activation of neurons and their integration into active engrams (“engram cells”). In this presentation, I will argue that ensemble integration may result from LTP, but also from cell-autonomous changes in membrane excitability. I propose that synaptic plasticity determines connectivity maps, whereas intrinsic plasticity — possibly separated in time — amplifies neuronal responsiveness and acutely drives engram integration. This proposal marks a move away from an exclusively synaptocentric toward a non-exclusive, neurocentric view of learning.