On discrimination learning trials which allowed subjects to press an information key when in doubt, retarded children made significantly more presses than control groups. Results confirmed the hypothesis that retarded children would be more outerdirected than normal children in a situation in which distractibility could not play a role. (Author/GO)

Evaluates the efficacy of two training procedures for eliminating selective stimulus control observed with three trainable mentally retarded children. In another experiment, improvements in stimulus control were not a function of varying degrees of difficulty between stimulus sets or of a prior history of discrimination training with the less…