Synaptic and network mechanisms of sparse and reliable visual cortical activity during nonclassical receptive field stimulation.
During natural vision, the entire visual field is stimulated by images rich in spatiotemporal structure. Although many visual system studies restrict stimuli to the classical receptive field (CRF), it is known that costimulation of the CRF and the surrounding nonclassical receptive field (nCRF) increases neuronal response sparseness. The cellular and network mechanisms underlying increased response sparseness remain largely unexplored. Here we show that combined CRF + nCRF stimulation increases the sparseness, reliability, and precision of spiking and membrane potential responses in classical regular spiking (RS(C)) pyramidal neurons of cat primary visual cortex. Conversely, fast-spiking interneurons exhibit increased activity and decreased selectivity during CRF + nCRF stimulation. The increased sparseness and reliability of RS(C) neuron spiking is associated with increased inhibitory barrages and narrower visually evoked synaptic potentials. Our experimental observations were replicated with a simple computational model, suggesting that network interactions among neuronal subtypes ultimately sharpen recurrent excitation, producing specific and reliable visual responses.
Department of Neurobiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA.
Bilal
B
Haider
Matthew R
MR
Krause
Alvaro
A
Duque
Yuguo
Y
Yu
Jonathan
J
Touryan
James A
JA
Mazer
David A
DA
McCormick
D000818:Animals; D002415:Cats; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D053444:Inhibitory Postsynaptic Potentials / Q000502:physiology; D007395:Interneurons / Q000378:metabolism; D008564:Membrane Potentials / Q000502:physiology; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons / Q000378:metabolism; D010775:Photic Stimulation / Q000379:methods; D009435:Synaptic Transmission / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*