title: Reversible deactivation of higher-order posterior parietal areas. II. Alterations in response properties of neurons in areas 1 and 2.
abstract: The role that posterior parietal (PPC) and motor cortices play in modulating neural responses in somatosensory areas 1 and 2 was examined with reversible deactivation by transient cooling. Multiunit recordings from neurons in areas 1 and 2 were collected from six anesthetized adult monkeys (Macaca mulatta) before, during, and after reversible deactivation of areas 5L or 7b or motor cortex (M1/PM), while select locations on the hand and forelimb were stimulated. Response changes were quantified as increases and decreases to stimulus-driven activity relative to baseline and analyzed during three recording epochs: during deactivation ("cool") and at two time points after deactivation ("rewarm 1," "rewarm 2"). Although the type of response change observed was variable, for neurons at the recording sites tested >90% exhibited a significant change in response during cooling of 7b while cooling area 5L or M1/PM produced a change in 75% and 64% of sites, respectively. These results suggest that regions in the PPC, and to a lesser extent motor cortex, shape the response characteristics of neurons in areas 1 and 2 and that this kind of feedback modulation is necessary for normal somatosensory processing. Furthermore, this modulation appears to happen on a minute-by-minute basis and may serve as the substrate for phenomena such as somatosensory attention.
authors.affiliation: Center for Neuroscience, University of California, Davis, California; Department of Psychology, University of California, Davis, California;
authors.forename: Adam B
authors.initials: AB
authors.lastname: Goldring
authors.affiliation: Center for Neuroscience, University of California, Davis, California; Department of Psychology, University of California, Davis, California;
authors.forename: Dylan F
authors.initials: DF
authors.lastname: Cooke
authors.affiliation: Department of Psychology, University of California, Davis, California;
authors.forename: Mary K L
authors.initials: MK
authors.lastname: Baldwin
authors.affiliation: Department of Psychology, University of California, Davis, California; Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California; and.
authors.forename: Gregg H
authors.initials: GH
authors.lastname: Recanzone
authors.affiliation: Center for Neuroscience, University of California, Davis, California;
authors.forename: Adam G
authors.initials: AG
authors.lastname: Gordon
authors.affiliation: Department of Biomedical Engineering, University of California, Davis, California.
authors.forename: Tingrui
authors.initials: T
authors.lastname: Pan
authors.affiliation: Department of Biomedical Engineering, University of California, Davis, California.
authors.forename: Scott I
authors.initials: SI
authors.lastname: Simon
authors.affiliation: Center for Neuroscience, University of California, Davis, California; Department of Psychology, University of California, Davis, California; lakrubitzer@ucdavis.edu.
authors.forename: Leah
authors.initials: L
authors.lastname: Krubitzer
mesh_terms: D000200:Action Potentials; D000818:Animals; D003080:Cold Temperature; D005260:Female; D006225:Hand / Q000502:physiology*; D008253:Macaca mulatta; D008297:Male; D008839:Microelectrodes; D009043:Motor Activity / Q000502:physiology; D009044:Motor Cortex / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D010812:Physical Stimulation; D013003:Somatosensory Cortex / Q000502:physiology; D055698:Touch Perception / Q000502:physiology*
keywords: cortical deactivation; feedback modulation; motor cortex; posterior parietal cortex; premotor cortex