Facilitating visual discrimination learning of moderately and severely mentally retarded children through...

The effectiveness of illuminating the positive stimulus after a correct response in visual discrimination training of moderately and severely mentally retarded children was investigated. An economical unit for illumination of stimuli was designed for purposes of the present investigation and for possible use in nonspeech communication training of mentally retarded children. In Experiment 1, the illumination of black stimuli on white backgrounds failed to facilitate discrimination learning. In Experiment 2, however, illumination of white stimuli on black backgrounds facilitated discrimination learning. The findings in the second experiment support the use of changes in illumination as an attention-influencing feature of nonspeech communication keyboards for retarded children.