DEVELOPMENT OF PERCEPTUAL-MOTOR INFORMATION PROCESSING

Abstract

The ability of severely and moderately retarded adults to improve their capacity to process information under specific training procedures was examined. A choice reaction time (RT)/movement time (MT) paradigm was followed where RT is defined as the period of time between the onset of a stimulus signal and the initiation of a response, and MT is the period between the initiation of the response and its completion. According to Fitts (1954) it is possible by way of these measures to estimate the processing capacities of individuals.;Retarded individuals consistently produce slower RTs and MTs than normals. Much evidence suggests that the processing impairments are organic in nature. If retarded individuals are to be expected to hold meaningful jobs, it would first be necessary to demonstrate that they can be trained to (i.e. have a fundamental capacity for) performing tasks such as those presented here.;Thirty retarded subjects with IQ scores of below 50 were randomly assigned to one of two treatment groups or to a practice-only group. The treatment groups differed with respect to the order in which one of two interventions was presented. Group 1 received the positive reinforcement-kinesthetic training order, while group 2 received the reverse. Group 3 controlled for the effects of sheer practice. Subjects received training for ten days; pre-test and post-test measures were taken.;The results substantially confirm the hypotheses whereby it could be concluded that: (1) the information processing capacity of retarded subjects as derived from RT and MT could be significantly improved under specific training procedures; (2) there is a lessened likelihood of improvement as task complexity increases; (3) the kinesthetic training-positive reinforcement order (Group 2) demonstrated the greatest gains; though, (4) the positive reinforcement-kinesthetic training order (Group 1) was significantly superior to controls where only practice was given.;These findings support the use of training procedures in the vocational habilitation of moderately and severely retarded individuals, particularly in jobs which were previously believed inaccessible to this population. In the process the notion of a structural limitation (i.e. deficit impervious to training) being present was substantially compromised. The implications for comprehensive treatment strategies were discussed and suggestions were made for the course of future research.