title: Membrane Potential Dynamics of Spontaneous and Visually Evoked Gamma Activity in V1 of Awake Mice.
abstract: Cortical gamma activity (30-80 Hz) is believed to play important functions in neural computation and arises from the interplay of parvalbumin-expressing interneurons (PV) and pyramidal cells (PYRs). However, the subthreshold dynamics underlying its emergence in the cortex of awake animals remain unclear. Here, we characterized the intracellular dynamics of PVs and PYRs during spontaneous and visually evoked gamma activity in layers 2/3 of V1 of awake mice using targeted patch-clamp recordings and synchronous local field potentials (LFPs). Strong gamma activity patterned in short bouts (one to three cycles), occurred when PVs and PYRs were depolarizing and entrained their membrane potential dynamics regardless of the presence of visual stimulation. PV firing phase locked unconditionally to gamma activity. However, PYRs only phase locked to visually evoked gamma bouts. Taken together, our results indicate that gamma activity corresponds to short pulses of correlated background synaptic activity synchronizing the output of cortical neurons depending on external sensory drive.
authors.affiliation: Swammerdam Institute for Life Sciences, Center for Neuroscience, Faculty of Science, University of Amsterdam, the Netherlands.|Department of Neurobiology, Yale University School of Medicine, New Haven, Connecticut, United States of America.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Perrenoud
authors.affiliation: Swammerdam Institute for Life Sciences, Center for Neuroscience, Faculty of Science, University of Amsterdam, the Netherlands.|Research Priority Program Brain and Cognition, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Cyriel M A
authors.initials: CM
authors.lastname: Pennartz
authors.affiliation: Swammerdam Institute for Life Sciences, Center for Neuroscience, Faculty of Science, University of Amsterdam, the Netherlands.|Team Waking, Lyon Neuroscience Research Center, INSERM U1028 - CNRS UMR5292 F-69008, Lyon, France.|University Lyon 1, F-69000, Lyon, France.
authors.forename: Luc J
authors.initials: LJ
authors.lastname: Gentet
mesh_terms: D000818:Animals; D065818:Gamma Rhythm; D007395:Interneurons / Q000378:metabolism; D008564:Membrane Potentials; D008822:Mice, Transgenic; D010320:Parvalbumins / Q000378:metabolism; D017966:Pyramidal Cells / Q000378:metabolism*; D014793:Visual Cortex / Q000378:metabolism*
chemical_list: D010320:Parvalbumins