title: Applying Transcranial Magnetic Stimulation (TMS) Over the Dorsal Visual Pathway Induces Schizophrenia-like Disruption of Perceptual Closure.
abstract: Perceptual closure ability is postulated to depend upon rapid transmission of magnocellular information to prefrontal cortex via the dorsal stream. In contrast, illusory contour processing requires only local interactions within primary and ventral stream visual regions, such as lateral occipital complex. Schizophrenia is associated with deficits in perceptual closure versus illusory contours processing that is hypothesized to reflect impaired magnocellular/dorsal stream. Perceptual closure and illusory contours performance was evaluated in separate groups of 12 healthy volunteers during no TMS, and during repetitive 10 Hz rTMS stimulation over dorsal stream or vertex (TMS-vertex). Perceptual closure and illusory contours were performed in 11 schizophrenia patients, no TMS was applied in these patients. TMS effects were evaluated with repeated measures ANOVA across treatments. rTMS significantly increased perceptual closure identification thresholds, with significant difference between TMS-dorsal stream and no TMS. TMS-dorsal stream also significantly reduced perceptual closure but not illusory contours accuracy. Schizophrenia patients showed increased perceptual closure identification thresholds relative to controls in the no TMS condition, but similar to controls in the TMS-dorsal stream condition. Conclusions of this study are that magnocellular/dorsal stream input is critical for perceptual closure but not illusory contours performance, supporting both trickledown theories of normal perceptual closure function, and magnocellular/dorsal stream theories of visual dysfunction in schizophrenia.
authors.affiliation: Department of Psychiatry, The Chaim Sheba Medical Center, TAU, 52621, Tel Hashomer, Israel. amiazr@gmail.com.
authors.forename: Revital
authors.initials: R
authors.lastname: Amiaz
authors.affiliation: Department of Psychology, The Gonda Multidisciplinary Brain Research Center, Bar Ilan University, 52900, Ramat Gan, Israel.
authors.forename: Dana
authors.initials: D
authors.lastname: Vainiger
authors.affiliation: Department of Psychiatry, The Chaim Sheba Medical Center, TAU, 52621, Tel Hashomer, Israel.
authors.forename: Ari A
authors.initials: AA
authors.lastname: Gershon
authors.affiliation: Department of Psychiatry, The Chaim Sheba Medical Center, TAU, 52621, Tel Hashomer, Israel.
authors.forename: Mark
authors.initials: M
authors.lastname: Weiser
authors.affiliation: Department of Psychology, The Gonda Multidisciplinary Brain Research Center, Bar Ilan University, 52900, Ramat Gan, Israel.|Department of Psychology, University of Hull, Hull, UK.
authors.forename: Michal
authors.initials: M
authors.lastname: Lavidor
authors.affiliation: Schizophrenia Research Center, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA.|Departments of Psychiatry and Neuroscience, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Javitt
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D010466:Perceptual Closure; D012559:Schizophrenia / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation; D014795:Visual Pathways
keywords: Illusory contours; Lateral occipital complex; Magnocellular; PO3/V3a; Perceptual closure; Vertex