Acquired distinctiveness: mediation and differentiation

This chapter provides a review of experiments (conducted for the most part with human participants) intended to show that perceptual learning will go on during the course of explicit discrimination training; that is, training in which the relevant stimuli are associated with different outcomes. The experiments show that the stimuli can acquire distinctiveness as a result of such training. Two theoretical explanations of this result are considered: one that attributes it to a change in the perceptual effectiveness of the stimuli (differentiation theory), and one that explains it in terms of...

This chapter provides a review of experiments (conducted for the most part with human participants) intended to show that perceptual learning will go on during the course of explicit discrimination training; that is, training in which the relevant stimuli are associated with different outcomes. The experiments show that the stimuli can acquire distinctiveness as a result of such training. Two theoretical explanations of this result are considered: one that attributes it to a change in the perceptual effectiveness of the stimuli (differentiation theory), and one that explains it in terms of association formation (mediation theory). It is concluded that most of the experimental results can be explained in associative terms but that this analysis does not preclude the possibility that differentiation goes on alongside associative mediation.