This study, which indicates that both age and variation in training affect children's concept formation, provides a basis for explaining the effect of age. Sixty-four 4- and 5-year-olds learned three novel concepts (animal-like, plant-like, and machine-like). Subjects were presented with either four different examples of each concept (multiple…

Trained preschoolers and adults on three sets of successive discriminations with stimuli labeled A, B, and R. Tested for derived stimulus-response relations and stimulus-stimulus relations. Adults displayed class-consistent B-R and A-B performances over all conditions. Children's display of class-consistent B-R performance varied by training…

The effect of stimulus familiarity on the comprehension of polar adjectives by preschool children was examined by administering a perceptual judgment task. The children's ability to indicate the correct object illustrating a particular word was assessed. Antonyms representing opposite dimensions of quantity, height, length, or size were presented.…