Interaction of Long- and Short-Term Memory on Selective Attention during Timbre Discrimination
The present study investigated the effects of short- and long-term memory on processes of selective attention during timbre discrimination. Pitch served as the distractor dimension, held constant on standard trials and deviating from the standard frequency on distractor trials. Short-term memory was operationalized as levels of covariate context: Within a block of trials, pitch deviants (p=.28) were either absent (baseline condition), varied orthogonally (filtering condition) or systematically (positive and perfect conditions) with timbre values. Long-term memory was operationalized as levels of psychophysical context: Within a block of trials, the range of pitch change was psychophysically equated with timbre change in the low-imbalance condition, tilted slightly in favor of the distractor dimension in the medium imbalance condition, or tilted strongly in favor of the distractor dimension in the high imbalance condition. We found that the effects of imbalance (long-term memory) on subjects' performance (accuracy and reaction time) were mediated by the degree of covariate context (short-term memory): The potency of the imbalance manipulation (low=best, high=worst) on distractor disruption (deviant minus standard) grew as the correlation between timbre and pitch increased from 0.0 (filtering), to .72 (positive) to 1.0 (perfect). The results suggest an intimate relationship between attention and memory, with attention acting to suppress or resolve both short- and the long-term influences of distractor activation on target processing.
Attention, Auditory, Memory, Medicine and Health Sciences, Psychiatry and Psychology
City University of New York - City College
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