Infants have shown variable success in quantity comparison tasks, with infants of a given age sometimes successfully discriminating numerical differences at a 2:3 ratio but requiring 1:2 and even 1:4 ratios of change at other times. The current explanations for these variable results include the two-systems proposal--a theoretical framework that…

In quantity discrimination tasks, adults, infants and animals have been sometimes observed to process number only after all continuous variables, such as area or density, have been controlled for. This has been taken as evidence that processing number may be more cognitively demanding than processing continuous variables. We tested this hypothesis…

Behavioral, psychophysiological, and neuropsychological studies have revealed large developmental differences in various learning paradigms where learning from positive and negative feedback is essential. The differences are possibly due to the use of distinct strategies that may be related to spatial working memory and attentional control. In…

The hypothesis testing abilities of 15 language impaired and 15 normally developing children matched for mental age were investigated using discrimination-learning tasks. Findings indicated the impaired children performed poorer than non-impaired children especially on the nonexplicit problems suggesting the deficits may be related to difficulties…

Strategies of kindergarten children in discrimination learning were studied in a factorial design with temporal placements of two introtact probes and two types of pretraining. Results support the expectation that the posttrial probe would improve the short-term efficiency of children in both pretraining conditions. (Author/MP)

A specially designed discrimination learning task was used to investigate whether the performance of kindergarten and first grade children could be improved through explicit training with a simple hypothesis-testing strategy. (Author/MP)

This experiment is concerned with delineating various aspects of pretraining that contributed to the improved hypothesis-testing strategies of 150 kindergarten children. (MP)

Subjects were trained against their initial dimensional preference in a two-dimensional simultaneous discrimination learning task. (RH)

This study, which assessed hypothesis-testing abilities using a discrimination-learning paradigm, found that 16 language-impaired primary-level children solved fewer problems than 16 controls equated on cognitive level, but the 2 groups used similar hypothesis types to solve the problems. Type of verbal feedback (explicit versus nonexplicit) did…

According to Hypothesis (H) theory, learning should be very difficult when the number of Hs the subject samples from is very large and/or the correct H is not available. These assumptions were tested with third- and fourth-grade children. In general, results supported these assumptions. (Author/MP)

Three studies of elementary school children's problem-solving procedures in intentional discrimination tasks are reported. Subjects were children selected from kindergarten and grades 2, 3, and 6. (Author/MP)

Recent studies have suggested that unusual visual processing in autism might stem from enhanced visual discrimination. Although there are also many anecdotal reports of auditory and tactile processing disturbances in autism these have received comparatively little attention. It is possible that the enhanced discrimination ability in vision in…

The process of forming operator schemata was studied in three experiments. In each experiment a greater amount of predictive information in a stimulus item increased the chance of selecting the operator accurately.