Separate detectors for simple and complex grating patterns?

A M Derrington; D R Badcock

doi:10.1016/0042-6989(85)90010-0

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Separate detectors for simple and complex grating patterns?

A M Derrington·D R Badcock

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Abstract

Grating having two sinusoidal components show a periodic variation in contrast which is visible as a "beat" pattern. The spatial frequency of the beat is the difference between the frequencies of the two components. Thresholds for a number of detection and discrimination tasks were measured using beat patterns of 1 c/deg (with components of 9 and 10 c/deg), and gratings of 1 and 10 c/deg. Temporal modulation at 6 Hz lowered detection thresholds for 1 c/deg gratings, but not for beats or 10 c/deg gratings. The effect of contrast on the range of temporal frequencies over which direction of movement can be discriminated differs for the three types of pattern: beats resemble neither low nor high spatial frequency gratings. Low and (for 2 of 3 observers) high spatial frequency gratings, but not beat patterns, are susceptible to a movement after effect induced by a low spatial-frequency grating. Beat patterns induce little or no movement after effect. We conclude that beat patterns are not detected by the same mechanisms that detect simple gratings.

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Figural Aftereffect Flicker Fusion Form Perception Humans Male Motion Perception Pattern Recognition, Visual Sensory Thresholds Time Factors Journal Article Research Support, Non-U.S. Gov't

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A M Derrington, D R Badcock. 1985. Separate detectors for simple and complex grating patterns?. https://doi.org/10.1016/0042-6989(85)90010-0

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