An institutionalized, retarded, adult male's response to verbal commands was increased through the use of positive control of a discriminative stimulus. Operant conditioning was noted as a possible means of enabling retarded individuals to acquire behaviors fundamental to a self-help repetoire. (Editor)

Tests the hypothesis that the effectiveness of discriminative stimuli as reinforcers is a function of the magnitude of the difference between them. (Author/RK)

The present experiment examined the choice behavior of humans during the learning of a reversal (R) shift as an empirical test of attentional explanations of the overtraining reversal effect. (Author/RK)

The prediction was confirmed that young children would experience more difficulty in learning to discriminate faces of another race than those of their own. Additional findings revealed that discrimination-learning performance with racial stimuli is related to a number of factors including developmental level, race of the subject, and race of the…

Conclusions from five experiments were: that the frequency of implicit associational responses has minimal effect on verbal-discrimination and two-category classification learning; and that the intrapair associations which do develop in verbal-discrimination learning are not critically involved in the making of those discriminations. (Authors/CB)

Experiments reported here confirm the finding that performance can actually improve as intradimensional variability increases. (Authors/MB)

Results showed that imagery and frequency factors have independent and additive effects in verbal discrimination learning. (Author)

Twenty trainable mentally handicapped adolescents and adults received 15 training sessions involving discrimination of pictured objects representing five categories from unrelated objects. (Author/GW)

The stimulus summation hypothesis predicts that the response strength of individual stimuli, when placed in combination, algebraically summate to produce a greater response strength than that of individual stimuli. (Author)

Color and form preferences of kindergarten, first and third grade Ss were tested using standard two-dimensional geometric forms. (Author)