Spatiotemporal filters in the detection of background modulation targets.
The background modulation method has been proposed as a useful test of early visual mechanisms [Biol. Cybern. 37, 77 (1980); Biol. Cybern. 47, 173 (1983)]. The task involves measuring detection thresholds for a luminous spot (increment) drifting over a spatially or temporally modulated background. The study explores the nature of the detecting mechanism in terms of spatial and temporal filters for both spatial and temporal background modulations. In both cases we find that thresholds can be explained by spatial contrast cues generated by the moving spot and that their spatiotemporal characteristics suggest detection by magnocellular processes.
McKendrick
A M
AM
Department of Optometry and Vision Sciences, University of Melbourne, Victoria, Australia. amckendrick@discoveriesinsight.org
Badcock
D R
DR
Vingrys
A J
AJ
D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology; D003463:Cues; D005260:Female; D006801:Humans; D008954:Models, Biological; D010775:Photic Stimulation / Q000379:methods; D012684:Sensory Thresholds; D013028:Space Perception / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology*