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…

This study investigated conditions leading to contextual control by stimulus topography over transfer of functions. Three 4-member stimulus equivalence classes, each consisting of four (A, B, C, D) topographically distinct visual stimuli, were established for 5 college students. Across classes, designated A stimuli were open-ended linear figures,…

In three experiments, match-to-sample procedures were used with undergraduates to establish arbitrary relational functions for three abstract visual stimuli. In the presence of samples A, B, and C, participants were trained to select the smallest, middle, and largest member, respectively, of a series of three-comparison arrays. In Experiment 1,…

The effects of different degrees of stimulus organization on subsequent generalization were studied with 120 fourth-grade children. (BRT)

Subjects of 4, 5, 7, and 20 years of age performed a speeded classification task designed to isolate sources of interference in visual selective attention. While subjects of all ages were unable to avoid processing distractors, older subjects were better able to inhibit distractor processing. (RH)

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)

Spontaneous and model-induced production of a valuational style of inquiry was studied in 128 third grade children. Provision of a favorable versus a neutral outcome-expectation, and sex of child failed to influence the results. All modeling groups displayed strong value-question increases over baseline which, without further tutelage, they…

The influence of frequency of occurrence of a visual stimulus on encoding processes is investigated, to discover what mechanisms allow cognitive processes to modify perceptual processes. Six experiments are described and the results are discussed. (MH)

In a permanently changing environment, it is by no means an easy task to distinguish potentially important events from negligible ones. Yet, to survive, every animal has to continuously face that challenge. How does the brain accomplish this feat? Building on previous work in "Drosophila melanogaster" visual learning, we have developed an…

With the advent of multi-screen capability in multi-media communication centers, it is possible to control the visual learning environment in a number of interesting ways. The basic assumption implicit in the concept of the multiple-image presentation is that it increases learning. A study tested the effect on learning of single- and…

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)

The combined theories of cue summation and stimulus generalization provide the theoretical model for this study. First, the study attempted to determine if supplementing a theoretical presentation of rhetorical principles with printed, audio, and audiovisual speech models would contribute to a significant increase in learning as evidence by…