Orientation-tuned spatial filters for texture-defined form.
Detection threshold for an orientation-texture-defined (OTD) test grating was elevated after adapting to an OTD grating of high orientation contrast. Threshold elevation was greatest for a test grating parallel to the adapting grating, and fell to zero for a test grating perpendicular to the adapting grating. We conclude that the human visual system contains an orientation-tuned neural mechanism sensitive to OTD form, and propose a model for this mechanism. We further propose that orientation discrimination for OTD bars and gratings is determined by the relative activity of these filters for OTD form.
Kwan
L
L
Department of Psychology, York University, Ontario, Canada.
Regan
D
D
D000221:Adaptation, Ocular; D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology; D005260:Female; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012399:Rotation; D012684:Sensory Thresholds / Q000502:physiology