Zusammenfassung
Velocity discrimination thresholds for drifting luminance gratings were measured as a function of the time interval between test and reference gratings, using a 2-interval, forced-choice procedure. Discrimination thresholds, expressed as Weber fractions (ΔV/V), were independent of interstimulus interval (ISIs) ranging from 1 to 30 sec, demonstrating perfect short-term retention of velocity ...
Zusammenfassung
Velocity discrimination thresholds for drifting luminance gratings were measured as a function of the time interval between test and reference gratings, using a 2-interval, forced-choice procedure. Discrimination thresholds, expressed as Weber fractions (ΔV/V), were independent of interstimulus interval (ISIs) ranging from 1 to 30 sec, demonstrating perfect short-term retention of velocity information. When a 3rd grating was briefly presented halfway through a 10-sec ISI, memory masking was observed. Discrimination thresholds in memory masking were unaffected by maskers of the same velocity but increased by 100% when test and masker velocity differed by a factor of 2. The results are interpreted with reference to a model where the short-term memory for simple stimulus attributes is assumed to be organized in terms of arrays of memory stores linked in a lateral inhibitory network.
Altmetric