title: The influences of visibility and anomalous integration processes on the perception of global spatial form versus motion in human amblyopia.
abstract: Do amblyopes demonstrate general irregularities in processes of global image integration? Or are these anomalies stimulus specific? To address these questions we employed directly analogous global-orientation and global-motion stimuli using a method that allows us to factor out any influence of the low-level visibility loss [Simmers, A. J., Ledgeway, T., Hess, R. F., & McGraw, P. V. (2003). Deficits to global motion processing in human amblyopia. Vision Research 43, pp. 729-738]. The combination of orientation and motion coherence thresholds reported here provides comparable psychophysical measures of global processing by spatial-sensitive and motion-sensitive mechanisms in the amblyopic visual system. The results show deficits in both global-orientation and global-motion processing in amblyopia, which appear independent of any low-level visibility loss, but with the most severe deficit affecting the extraction of global motion. This provides evidence for the existence of a dominant temporal processing deficit in amblyopia.
authors.affiliation: Department of Optometry and Visual Science, Applied Vision Research Centre, The Henry Wellcome Laboratories for Vision Sciences, City University, London EC1V OHB 22, UK. a.simmers@city.ac.uk
authors.forename: Anita J
authors.initials: AJ
authors.lastname: Simmers
authors.forename: Tim
authors.initials: T
authors.lastname: Ledgeway
authors.forename: Robert F
authors.initials: RF
authors.lastname: Hess
mesh_terms: D000328:Adult; D000550:Amblyopia / Q000503:physiopathology / Q000523:psychology*; D015350:Contrast Sensitivity; D005556:Form Perception; D006801:Humans; D009039:Motion Perception; D009949:Orientation; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D011930:Reaction Time; D012684:Sensory Thresholds; D014792:Visual Acuity