Metacontrast with masks varying in spatial frequency and wavelength.
In a metacontrast masking paradigm, adult subjects were required to detect briefly presented target lines followed at various delays by a flanking mask varying in spatial frequency and wavelength. Detection accuracy, the dependent measure, was recorded as a function of the delay of the mask. The results showed that long wavelength masks produced maximum masking at a relatively short delay, while short wavelength masks produced maximum masking at a relatively long delay. Results are discussed within the framework of transient/sustained (magnocellular/parvocellular) theory of visual processing, and suggest that low spatial frequency channels respond with shorter latency and/or faster rise time to short wavelength stimuli, and high spatial frequency channels respond with greater sensitivity to long wavelength stimuli.
Williams
M C
MC
Department of Psychology, University of New Orleans, LA 70148.
Breitmeyer
B G
BG
Lovegrove
W J
WJ
Gutierrez
C
C
D000328:Adult; D003118:Color Perception / Q000502:physiology*; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D006801:Humans; D010470:Perceptual Masking / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors