Motion aftereffect duration is not changed by perceptual learning: Evidence against the representation modification hypothesis

Abstract:

The representation modification hypothesis of perceptual learning attributes the practice-induced improvements in sensitivity and/or discriminability to changes in the early visual areas. We used motion aftereffects (MAE) to probe the representations of motion direction. In two experiments, 4 practice sessions on a fine direction-discrimination task caused large stimulus-specific improvements in d' but no significant stimulus-specific changes in either static or dynamic MAE duration at posttest relative to a pretest. Power analysis indicated that the data were approximately 100 times more likely given the hypothesis of no MAE change than the hypothesis of a 10% relative change. In light of converging evidence in the MAE literature, this suggests that little or no change occurred in the cortical representations of visual motion up to and including area MT. The task specificity of the learning effect challenges the representation modification hypothesis and supports an alternative -- selective reweighting.

Keywords: perceptual learning, motion aftereffect, representation modification, selective reweighting, specificity

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Perceptual Learning Project

Matlab Report

In the process of analyzing the data, developing the models, and fitting them to the data, we wrote various Matlab scripts. These scripts generated HTML reports via Matlab's "publish" feature. The most recent report is made available here. Use the Back button in your browser to return to this page.

• MAES02_ANOVA.html -- ANOVAs and power analyses for Experiments 1 and 2.