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)

Efficiency was compared between three procedures for sequencing examples with minimal stimulus variation between adjacent positive and negative examples: dynamic, static, and static with maximal differences between pairs. For young children, increasing relevant feature saliency and altering a single stimulus to generate examples reduced training…

The investigation of interactions between the abilities of stimulus discrimination and simple learning and two instructional variables (discrimination difficulty and degree of overlearning) with 27 mentally retarded adolescents found an interaction between stimulus discrimination and the number of words presented at one time for learning…

Simple discriminations are involved in many functional skills; additionally, they are components of conditional discriminations (identity and arbitrary matching-to-sample), which are involved in a wide array of other important performances. Many individuals with severe disabilities have difficulty acquiring simple discriminations with standard…

Based on the author's M.A. dissertation submitted to the University of Illinois, Urbana.

This report summarizes research concerning stimulus analyzing mechanisms, giving the main experimental findings and theoretical developments. Most of the data and the experimental findings are to be found in the 89 publications listed in the bibliography. The research is discussed under five main headings: (1) shape recognition, (2) selective…

Ten mildly retarded young adult males and nonretarded subjects matched for chronological age or mental age were required to recognize both verbal and nonverbal stimuli presented tachistoscopically. Results of a backward visual masking paradigm varying stimulus onset asynchrony (SOA) indicated the retarded subjects performed poorer at the longest…

Four studies compared static versus dynamic presentations of examples and nonexaples of the concepts "diagonal" and "conves," with nonhandicapped preschoolers, mildly handicapped primary students, and severely handicapped adults. Ss taught with a dynamic presentation learned the discrimination in significantly fewer trials, with performance either…

We have previously reported that sound sequence discrimination learning requires cholinergic inputs to the auditory cortex (AC) in rats. In that study, reward was used for motivating discrimination behavior in rats. Therefore, dopaminergic inputs mediating reward signals may have an important role in the learning. We tested the possibility in the…

Previous studies have shown that after being trained on A-B and A-C match-to-sample tasks, adults match not only same-class B and C stimuli (equivalence) but also BC compounds with same-class elements and with different-class elements (BC-BC). The assumption was that the BC-BC performances are based on matching equivalence and nonequivalence…

This experiment examined the effects of reinforcement probability on resistance to change of remembering and response rate. Pigeons responded on a two- component multiple schedule in which completion of a variable-interval 20-s schedule produced delayed matching-to-sample trials in both components. Each session included four delays (0.1 s, 2 s, 4…

Stimulus overselectivity refers to the phenomenon whereby stimulus control over behavior is exerted only by a limited subset of the total number of stimuli present during discrimination learning. It often is displayed by individuals with autistic spectrum disorders or learning disabilities, but is not exclusive to those groups. The present studies…

Studies hypothesized and tested that a judge's discriminal process is a sample from a normal distribution of all possible discriminal processes for the MMPI stimulus set; that standard deviations of two distributions of binary MMPI decisions are equal; and that discriminative capacities of judges remain fixed from one decision session to the next.…

Research supported by a U.S. Public Health Service fellowship grant and by grant No. 01368-04 from the National Institute of Child Health and Human Development.