title: Layer 4 fast-spiking interneurons filter thalamocortical signals during active somatosensation.
abstract: We rely on movement to explore the environment, for example, by palpating an object. In somatosensory cortex, activity related to movement of digits or whiskers is suppressed, which could facilitate detection of touch. Movement-related suppression is generally assumed to involve corollary discharges. Here we uncovered a thalamocortical mechanism in which cortical fast-spiking interneurons, driven by sensory input, suppress movement-related activity in layer 4 (L4) excitatory neurons. In mice locating objects with their whiskers, neurons in the ventral posteromedial nucleus (VPM) fired in response to touch and whisker movement. Cortical L4 fast-spiking interneurons inherited these responses from VPM. In contrast, L4 excitatory neurons responded mainly to touch. Optogenetic experiments revealed that fast-spiking interneurons reduced movement-related spiking in excitatory neurons, enhancing selectivity for touch-related information during active tactile sensation. These observations suggest a fundamental computation performed by the thalamocortical circuit to accentuate salient tactile information.
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, USA.
authors.forename: Jianing
authors.initials: J
authors.lastname: Yu
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, USA.
authors.forename: Diego A
authors.initials: DA
authors.lastname: Gutnisky
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, USA.|University of Southern California, Los Angeles, California, USA.
authors.forename: S Andrew
authors.identifier: 0000-0003-3498-0388
authors.initials: SA
authors.lastname: Hires
authors.affiliation: Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, USA.
authors.forename: Karel
authors.initials: K
authors.lastname: Svoboda
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D004558:Electric Stimulation / Q000379:methods; D007395:Interneurons / Q000502:physiology*; D051379:Mice; D009068:Movement / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000379:methods; D010812:Physical Stimulation / Q000379:methods; D013003:Somatosensory Cortex / Q000502:physiology*; D013788:Thalamus / Q000502:physiology; D014110:Touch / Q000502:physiology; D014738:Vibrissae / Q000502:physiology*