title: Effects of co-activation on cortical organization and discrimination performance.
abstract: We used fMRI to investigate the effects of tactile co-activation on the topographic organization of the human primary somatosensory cortex (SI). Behavioral consequences of co-activation were studied in a psychophysical task assessing the mislocalization of tactile stimuli. Co-activation was applied to the index, middle and ring fingers of the right hand either synchronously or asynchronously. Cortical representations for synchronously co-activated fingers moved closer together, whereas cortical representations for asynchronously co-activated fingers became segregated. Behaviorally, this pattern coincided with an increased and reduced number of mislocalizations between synchronously and asynchronously co-activated fingers, respectively. Thus, both synchronous and asynchronous coupling of passive tactile stimulation is able to induce short-term cortical reorganization associated with functionally relevant changes.
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstrasse 29, 72074 Tübingen, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Pilz
authors.forename: Ralf
authors.initials: R
authors.lastname: Veit
authors.forename: Christoph
authors.initials: C
authors.lastname: Braun
authors.forename: Ben
authors.initials: B
authors.lastname: Godde
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D010812:Physical Stimulation; D011597:Psychomotor Performance / Q000502:physiology*; D011601:Psychophysics / Q000379:methods; D013003:Somatosensory Cortex / Q000098:blood supply / Q000502:physiology*; D014110:Touch / Q000502:physiology*
chemical_list: D010100:Oxygen