Reversal and non-reversal shifts in discrimination learning in retardates.

Abstract
Mentally defective children were trained on a discrimination problem with either color relevant and form irrelevant, or the opposite. One group had the irrelevant cue varied randomly during training; the other had a constant irrelevant cue. Following training, Ss learned either a simple reversal, a new problem with stimuli from the same relevant dimension (intradimensional shift), or a new problem with stimuli from the irrelevant training dimension (extradimensional shift). Extradimensional shift was significantly more difficult than either reversal or intradimensional shift. Reversal and intradimensional shift performance did not differ. Results were interpreted as consistenl with observing response theory, but suggestive of changes for a verbal mediation theory.