An attentional model of dimensional contrast.

In this article, the authors introduce a model of dimensional stimulus control designed to explain dimensional contrast effects. The model suggests that dimensional contrast is the result of the nonuniform allocation of limited attentional resources during discrimination training. Attention in the model is conceived as a gradient that extends throughout a spatial representation of stimuli. The authors examine the results of 5 experiments to assess the quality of fit of the model and its theoretical implications. Variations in training procedures, such as changing presentation probability of stimuli, changing the distribution of training stimuli, and changing the relative difficulty of discrimination, can all be accounted for by differences in the allocation of attentional resources. The good fit of the model indicates that attentional limitations may play an important role in stimulus control phenomena such as dimensional contrast. (PsycINFO Database Record (c) 2010 APA, all rights reserved)