title: The influence of stimulus luminance and contrast on hyperacuity thresholds for oscillatory movement.
abstract: Hyperacuity thresholds for oscillatory movement were determined under conditions of decreased contrast and decreased luminance. Responses were found to be resistant to contrast reduction down to 15%; below this level thresholds increased. The contrast response function is thus similar to that of the magnocellular channel of the visual system. Systematic reduction in luminance caused a corresponding rise in thresholds. It is suggested that this effect is due to undersampling of the retinal image as a result of a lowered quantal absorption and an increase in critical duration of temporal integration at lower levels of luminance.
authors.affiliation: Department of Optometry, University of Bradford, UK.
authors.forename: R
authors.initials: R
authors.lastname: Watkins
authors.forename: T
authors.initials: T
authors.lastname: Buckingham
mesh_terms: D015350:Contrast Sensitivity / Q000502:physiology*; D005556:Form Perception / Q000502:physiology; D006801:Humans; D008027:Light; D009039:Motion Perception / Q000502:physiology*; D010783:Photometry; D012684:Sensory Thresholds / Q000502:physiology; D013997:Time Factors; D014792:Visual Acuity / Q000502:physiology*