Perceptual learning mechanisms with single-stimulus exposure.

The present manuscript briefly reviews associative and non-associative theories of perceptual learning and presents two experiments (1a and 1b) examining the extent to which retrospective revaluation (RR) and a restoration of perceptual effectiveness (RPE) can account for the enhanced discriminability that experience with a single stimulus produces. In both experiments participants were exposed to compound visual stimuli BX, CY, and DZ in an online video-game method followed by conditioning with compound stimuli AX and AY. In Experiment 1a generalization to compounds BX, DX, BY, and DY was assessed. Generalization to compounds involving B, either BX or BY, was less than to DX or DY. The result possibly reflected enhanced salience of B, or that B had become inhibitory for the outcome through RR. Experiment 1b used a retardation test comparing compound stimuli BW and DW. Acquisition was more effective with BW than DW, suggesting that B had become more perceptually effective, resulting in it producing more external inhibition than D in Experiment 1a, and allowing it to condition more rapidly in Experiment 1b. Results are discussed with respect to current theories of perceptual learning and are consistent with a restoration of perceptual effectiveness.