An Investigation of the Nature of Non-Directive Psychotherapy

An experiment was performed to assess the effects of mental age (MA) and external cues on response inhibition in the mentally retarded. Twelve Ss were presented with an experimental task which required that they withhold responding for five or more seconds before pressing a key to obtain reinforcement. For half the Ss the key was lighted (cued) during the waiting interval, while it was unlighted (uncued) for the other half. The results indicate that (a) response inhibition increased with MA and (b) MA differences might have been due to an inability to mediate the delay interval. The results were interpreted in terms of possible mediating mechanisms and implications for training inhibitory performance in the mentally retarded.