title: Neural mechanisms of selective attention in the somatosensory system.
abstract: Selective attention allows organisms to extract behaviorally relevant information while ignoring distracting stimuli that compete for the limited resources of their central nervous systems. Attention is highly flexible, and it can be harnessed to select information based on sensory modality, within-modality feature(s), spatial location, object identity, and/or temporal properties. In this review, we discuss the body of work devoted to understanding mechanisms of selective attention in the somatosensory system. In particular, we describe the effects of attention on tactile behavior and corresponding neural activity in somatosensory cortex. Our focus is on neural mechanisms that select tactile stimuli based on their location on the body (somatotopic-based attention) or their sensory feature (feature-based attention). We highlight parallels between selection mechanisms in touch and other sensory systems and discuss several putative neural coding schemes employed by cortical populations to signal the behavioral relevance of sensory inputs. Specifically, we contrast the advantages and disadvantages of using a gain vs. spike-spike correlation code for representing attended sensory stimuli. We favor a neural network model of tactile attention that is composed of frontal, parietal, and subcortical areas that controls somatosensory cells encoding the relevant stimulus features to enable preferential processing throughout the somatosensory hierarchy. Our review is based on data from noninvasive electrophysiological and imaging data in humans as well as single-unit recordings in nonhuman primates.
authors.affiliation: Department of Neuroscience, Brown University, Providence, Rhode Island; The Zanvyl Krieger Mind/Brain Institute, The Johns Hopkins University, Baltimore, Maryland; and The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland manuel_gomez-ramirez@brown.edu.
authors.forename: Manuel
authors.identifier: 0000-0002-1017-5256
authors.initials: M
authors.lastname: Gomez-Ramirez
authors.affiliation: The Zanvyl Krieger Mind/Brain Institute, The Johns Hopkins University, Baltimore, Maryland; and.
authors.forename: Kristjana
authors.initials: K
authors.lastname: Hysaj
authors.affiliation: The Zanvyl Krieger Mind/Brain Institute, The Johns Hopkins University, Baltimore, Maryland; and The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Ernst
authors.initials: E
authors.lastname: Niebur
mesh_terms: D000818:Animals; D001288:Attention / Q000502:physiology*; D006801:Humans; D016571:Neural Networks, Computer; D009474:Neurons / Q000502:physiology; D013003:Somatosensory Cortex / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*
keywords: cross-modal; noise correlations; somatosensation; spike synchrony; spike-count correlations