How strategies affect learning of categories that lack necessary and sufficient attributes is explored. The authors propose that strategy variations induced by instructions affect only the amount of information represented about attributes, not processes operating on representations. An experiment required subjects to classify schematic faces into…

The discrimination of minimally paired speech sounds by seven severely retarded children (mean age 3.2 years, and mean IQ 38.4) was compared with the discrimination performance of eight normally developing 7-month-old infants. (Author/PHR)

Forty elementary children (six and nine year olds) and 20 college students were required to discriminate identical pairs of visual stimuli from mirror images. It was hypothesized that a key factor in performance would be the extent to which orientation was a functionally significant attribute of the stimuli. (Author/MP)

The efficacy of a six-week training program for teaching 20 educable mentally retarded elementary children the language skills prerequisite to distinguishing between the relevant and irrelevant features of a task was evaluated. (Author/CL)

Studies the effects of perceptual salience on performance in problems requiring the coordination of information. Subjects were groups of children, younger adults, and older adults. For each of the age groups, those problems containing the most salient information were solved faster and more accurately than problems containing the least salient…

Field independence, visual analysis, and spatial visualization were investigated and social communication skills were assessed in two groups of 25 first graders (chosen for either high or low verbal ability). (Author/PHR)

Psychophysical procedures provide the simplest method for studying time discrimination of animals. This experiment examines the psychological threshold of rats in estimating the time of occurrence of an event and how they adjust their behavior accordingly. Further research may determine the theoretical implications for both animals and people.…

Problem drinkers in the community were subjects in a study that evaluated the therapeutic potential of learning techniques in changing abusive drinking patterns and achieving moderation. The authors conclude that moderation is a more attainable and feasible goal for problem drinkers than for chronic alcoholics. (Author)

Examined effects of a click signaling arrival of a visual stimulus to be timed on temporal discrimination in 3-, 5-, and 8-year-olds. Found that in all groups, the proportion of long responses increased with the stimulus duration, although the steepness of functions increased with age. Stimulus duration was judged longer with than without the…

Two studies examined whether infants' category discrimination in an object-examination task was based solely on an ad hoc analysis of perceptual similarities among the experimental stimuli. Findings indicated that 10- to 11-month- olds' responses varied systematically only with the presence of a category change, but not with the degree of…

Two time-delay conditions for teaching complex visual discriminations to 14 normal preschoolers, 12 with mild mental retardation, and 11 with moderate mental retardation were compared. Results indicated that for all populations and stimuli, time delay of multiple dynamic distinctive-feature prompts produced learning, while time delay of the single…

Investigates the dominance of global versus local visual properties in four-month-old infants as a function of individual differences in fixation duration. Suggests that long-looking infants process visual information more slowly than short-looking infants, and there may be qualitative differences in the manner in which the two groups of infants…

Two experiments with a total of 17 adolescents or adults with severe mental retardation evaluated the potential of exclusion procedures (selection of an undefined object in comparison with a defined object) as a means of training basic naming skills. Reliable exclusion and naming performance were demonstrated in nearly all subjects. (DB)

Sixteen individuals (ages 7-18) with moderate or severe mental retardation were taught to identify 2 comparative discriminations by a static or dynamic presentation procedure. No differences in percentage of unprompted correct responses were found between the two procedures in training, generalization, or maintenance. (Author/JDD)

Seven adults with severe to profound mental retardation participated in match-to-sample discrimination training under three conditions. Results indicated that error-correction procedures improve performance through negative reinforcement; that error correction may serve multiple functions; and that, for some subjects, trial repetition enhances…