Allan Gulledge, PhD
Associate Professor of Molecular and Systems Biology
The Geisel School of Medicine at Dartmouth College
Coordinated pre- and postsynaptic cholinergic modulation selectively drives corticofugal networks
Acetylcholine (ACh) acts as a powerful neuromodulator in the neocortex during wakefulness and paradoxical sleep (i.e., dream states). Yet how ACh regulates information flow through cortical circuits is not well understood. We and others have previously shown that ACh preferentially excites deep-layer pyramidal neurons that project to the thalamus and brainstem (pyramidal tract, or “PT” neurons) relative to neighboring intratelencephalic (IT) neurons. We now share data demonstrating that ACh acts presynaptically to reduce glutamate release for some excitatory (glutamatergic) afferents to the cortex while other afferents are spared. Further, we show that ACh enhances local excitatory network activity to selectively drive PT neurons. Via these coordinated pre- (greater excitatory drive to PT neurons) and postsynaptic (increased PT excitability) mechanisms, we propose that ACh acts to selectively enhance corticofugal output.
Invited by Pierre-Pascal Lenck-Santini
Inmed meeting room, Monday, September 19th – 11 a.m