A shift in generalization gradients away from S+ and towards stimuli on the opposite end of the stimulus dimension from S- is a well established phenomenon in the laboratory, occurring with humans and nonhumans and with a wide range of stimuli. The phenomenon of gradient shifts has also been observed to have an analogous relationship to a variety…

According to the composite-stimulus control model (Weiss, 1969, 1972b), an individual discriminative stimulus (S[superscript D]) is composed of that S[superscript D]'s on-state plus the off-states of all other relevant S[superscript D]s. The present experiment investigated the reversibility of composite-stimulus control. Separate groups of rats…

Hearing-impaired 6- to 13-year-olds (N=24), trained to discriminate between two stimulus complexes differing in shape, direction, and number, were asked to discriminate between individual characteristics in all possible pair combinations. General failure to respond to all characteristics equally suggested that hearing-impaired children tend to be…

Tests the effects of stimulus variability on overgeneralization and overdiscrimination errors in children and adults. The subjects (n=64), adults and five-, seven-, and nine-year-old children, participated in a visual discrimination task. (CM)

An evaluation of selective generalization of habituation on the basis of meaningful categories of stimuli. Also explored are the sex differences in conceptual generalization of habituation. Subjects were 36 toddlers with a mean age of 40 months. (SDH)

Looking times of 36 children were recorded during subject-controlled presentation of slides in order to determine whether the existence of simple categories in 3-year-olds can be inferred from habituation data, and to determine any sex differences in conceptual generalization of habituation. Habituation was demonstrated over repeated presentation…