title: Functional correlates of optic flow motion processing in Parkinson's disease.
abstract: The visual input created by the relative motion between an individual and the environment, also called optic flow, influences the sense of self-motion, postural orientation, veering of gait, and visuospatial cognition. An optic flow network comprising visual motion areas V6, V3A, and MT+, as well as visuo-vestibular areas including posterior insula vestibular cortex (PIVC) and cingulate sulcus visual area (CSv), has been described as uniquely selective for parsing egomotion depth cues in humans. Individuals with Parkinson's disease (PD) have known behavioral deficits in optic flow perception and visuospatial cognition compared to age- and education-matched control adults (MC). The present study used functional magnetic resonance imaging (fMRI) to investigate neural correlates related to impaired optic flow perception in PD. We conducted fMRI on 40 non-demented participants (23 PD and 17 MC) during passive viewing of simulated optic flow motion and random motion. We hypothesized that compared to the MC group, PD participants would show abnormal neural activity in regions comprising this optic flow network. MC participants showed robust activation across all regions in the optic flow network, consistent with studies in young adults, suggesting intact optic flow perception at the neural level in healthy aging. PD participants showed diminished activity compared to MC particularly within visual motion area MT+ and the visuo-vestibular region CSv. Further, activation in visuo-vestibular region CSv was associated with disease severity. These findings suggest that behavioral reports of impaired optic flow perception and visuospatial performance may be a result of impaired neural processing within visual motion and visuo-vestibular regions in PD.
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Boston, MA, USA.
authors: Deepti
authors: D
authors: Putcha
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Boston, MA, USA ; Department of Psychology, University of New Hampshire Durham, NH, USA.
authors: Robert S
authors: RS
authors: Ross
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Boston, MA, USA.
authors: Maya L
authors: ML
authors: Rosen
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA.
authors: Daniel J
authors: DJ
authors: Norton
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA.
authors: Alice
authors: A
authors: Cronin-Golomb
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Boston, MA, USA.
authors: David C
authors: DC
authors: Somers
authors: Department of Psychology, Center for Memory and Brain, Boston University Boston, MA, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Boston, MA, USA.
authors: Chantal E
authors: CE
authors: Stern
keywords: CSv; MT+; Parkinson’s disease; fMRI; optic flow