Stimulus-specific mechanisms of visual short-term memory.
The retention of spatial information in visual short-term memory was assessed by measuring spatial frequency discrimination thresholds with a two-interval forced-choice task varying the time interval between the two gratings to be compared. The memory of spatial frequency information was perfect across 10-sec interstimulus intervals. Presentation of a "memory masker" grating during the interstimulus interval may interfere with short-term memory. This interference depends on the relative spatial frequency of the test and masker gratings, with maximum interference at spatial frequency differences of 1-1.5 octaves and beyond. This range of interference with short-term memory is comparable to the bandwidth of sensory masking or adaptation. A change of the relative orientation of test and masker gratings does not produce interference with spatial frequency discrimination thresholds. These results suggest stimulus-specific interactions at higher-level representations of visual form.
Magnussen
S
S
Vision Laboratory, University of Oslo, Norway.
Greenlee
M W
MW
Asplund
R
R
Dyrnes
S
S
D004192:Discrimination, Psychological / Q000502:physiology; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology; D012684:Sensory Thresholds / Q000502:physiology; D013997:Time Factors