Effects of stimulus mode on the acquisition, transfer, and generalization of categories by severely mentally retarded children and adolescents.

The effects of object training and photograph training on comprehension of category labels by severely mentally retarded children were explored. Relatively simple tasks (acquisition of trained examples and transfer between modes) and relatively difficult tasks (generalization to novel examples in the training mode and in the other mode) were both included. Results indicated that acquisition and transfer did not differ, yet generalization was significantly more accurate with objects than with photographs. Furthermore, generalization was significantly above chance for objects but not for photographs. Results were discussed in reference to discriminability between the two modes and possible constraints of decision-making demands on generalization performance.