Identity Matching-To-Sample and ASD: Effect of Pairs of Identical Stimuli as a Consequence for Correct Matching

In a replication of a study by Gomes (2011), the effect of the presentation of pairs of identical stimuli after correct matching was assessed in Typical and Multi-sample matching-to-sample tasks. Twentyfour individuals with Autism Spectrum Disorder (ASD) were distributed in two conditions, each with three blocks of trials: Typical, Multi-sample and a mix of both trial types. The order of exposure was counterbalanced across participants within a condition. The fi rst two blocks of trials consisted of both training and testing trials; the third block consisted only of test trials. In Condition 1, the sample stimulus was removed from the screen upon correct matching; in Condition 2 correct matching was followed by presentation of a compound stimulus with two equal elements. Results showed that, regardless of experimental condition and order of exposure to matching-to-sample tasks, percentage of correct responses was higher in Typical Matching test trials. In Condition 2, scores were greater than in Condition 1. For individuals with ASD, control by the relation of identity may be affected by the visual organization of the tasks and by other procedural variables such as the consequences for matching responses, response topography (clicking or dragging) and the training criterion.