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Biomedical subjects

R Kail

Publications and source records attributed to R Kail.

29 records · Page 2Linked to original sources
PubMed1986

The impact of extended practice on rate of mental rotation.

9-, 13-, and 20-year-olds were tested on 3840 trials of a mental rotation task in which they judged if pairs of stimuli presented in different orientations were identical or mirror images. Response time increased linearly as a function of the difference in orientation of the stimuli, and the slope of this function was used to estimate rate of mental rotation. At all ages, mental rotation became faster over trials. Age differences in rate of mental rotation were eliminated after approximately 1500 trials. At all ages the influence of practice was well characterized by hyperbolic and power functions. Furthermore, children's and adolescents' data were well fit by hyperbolic and power functions in which most of the parameters of those functions were constrained to adults' values. These results are discussed in terms of possible mechanisms underlying the impact of practice.

Adolescent↗
PubMed1986

Sources of age differences in speed of processing.

3 experiments were conducted to study developmental change in the speed of cognitive processes. In Experiment 1, subjects ranging in age from 8 to 21 years were tested on a mental rotation task in which they judged whether pairs of letters presented at different orientations were identical or mirror images, and on a name retrieval task in which they judged if pairs of pictures were identical physically or had the same name. Increases with age in the speed of mental rotation and speed of name retrieval were both well described by exponential functions, and the rate of developmental change was comparable for the 2 tasks. Experiment 2 confirmed that age changes in rate of mental rotation are well described by an exponential function. Experiment 3 demonstrated, on a mental rotation task, a perfect correlation across conditions between children's mean response times and adults' mean response times for corresponding conditions. These results are interpreted as indicating that age differences in speed of processing are due, at least in part, to a central limiting mechanism that increases with age.

Adolescent↗
PubMed1984

Syntactic and conceptual factors in children's understanding of metaphors.

A multiple-choice listening task was designed in which 7- and 9-year-old children (n = 30 per group) were presented with nine instances of four different types of metaphoric sentences: perceptual-predicative, psychological-predicative, perceptual-proportional, and psychological-proportional. When factors of memory and attention, sentence length, semantics, and novelty were controlled for, proportional metaphors proved to be significantly more difficult than predicative, but perceptual did not differ from psychological in ease of understanding. No interactions were significant. Nine-year-olds demonstrated metaphoric understanding superior to that of 7-year-olds, despite the fact that children of both ages were familiar with the underlying semantic features of the metaphors and understood all key words at a literal level. Implications for future research are discussed.

Attention↗
PubMed1984

Unconstrained retrieval from semantic memory.

The present study was designed to examine developmental change in the processes used to retrieve lexical information from semantic memory. We asked 8-, 12-, and 21-year-olds to name as many animals and pieces of furniture as they could, in separate 7-min intervals. The principal results were the following: (1) the number of items retrieved increased with age, but at all ages retrieval declined hyperbolically over the 7-min interval; (2) analysis of the time between retrieval of successive items indicated that older individuals retrieved larger clusters of items, but that the number of clusters retrieved did not vary with age; and (3) at all ages prototypic category members were retrieved first, followed by typical (but not prototypic) and atypical category members. The results are explained in terms of a model in which the information in semantic memory changes with age, but the processes used to retrieve that information do not.

Adult↗
PubMed1983

[Heart surgery in a female patient with blood group Oh (Bombay phenotype)].

A 62-year-old woman with stenosing coronary artery disease had the rare blood group Oh (Bombay phenotype). After prophylactic deep-freeze conservation of autologous blood, direct myocardial revascularization was successfully accomplished under extracorporeal circulation. Three deep-freeze units of erythrocyte concentrates were used. Both operation and postoperative wound healing progressed without complication.

ABO Blood-Group System↗
PubMed1983

Algorithms for processing spatial information.

Pairs of stimuli taken from a psychometric measure of spatial aptitude were shown to 9-year-olds, 13-year-olds, and adults. The stimuli in pairs were (a) either identical or mirror images, and (b) presented in orientations that differed by 0-150 degrees. Individuals judged, as rapidly as possible, if the stimuli in a pair would be identical or mirror images if presented at the same orientation. In Experiment 1, in which the stimuli were letter-like characters, at all ages most persons solved the problems using an algorithm in which an individual encodes the stimuli in working memory, mentally rotates one stimulus to the orientation of the other, compares them to determine if they are identical, and responds. In Experiment 2, the stimuli were multielement flags; here, the modal algorithm for both 9- and 13-year-olds differed from the previously described algorithm in that if the comparison process revealed that the stimuli were dissimilar, individuals did not respond immediately, but continued processing until a self-imposed deadline was reached. Among adults, the modal algorithm was the same one used in Experiment 1. Results are discussed in terms of the roles of encoding in contributing to the use of a particular algorithm.

Adolescent↗
PubMed1983

Picture naming in language-impaired children.

A picture-naming task was used to examine word-finding problems in language-impaired children. The subjects included 20 language-impaired children, 20 normal children matched to the language-impaired children for chronological age, and 20 normal children matched to the language-impaired children on a composite index of language age. Children were shown 64 pictures of objects and asked to name each as rapidly as possible. The principal findings were that (a) pictures of objects with more frequently occurring names were named more rapidly than pictures of objects with less frequently occurring names; (b) language-imparied children named pictures less rapidly than their chronological-age peers but more rapidly than their language-age peers; and (c) the effects of frequency of occurrence on naming time were comparable for all three groups of children. Factors that may have accounted for the findings are discussed.

Child↗
PubMedDate not supplied

Brief report: speed of information processing in children with insulin-dependent diabetes mellitus.

OBJECTIVE: To determine whether children with insulin-dependent diabetes mellitus (IDDM) process information more slowly than children who do not have diabetes. METHODS: We tested 31 children with early onset and longer duration of IDDM, 35 with later onset and briefer duration of IDDM, and 36 comparison children without diabetes. They were administered five tasks requiring rapid responding that assessed a range of cognitive processes. RESULTS: On most tasks, children in the three groups were quite similar in the accuracy and speed of performance. Furthermore, for children in the diabetic groups, disease-related variables were unrelated to accuracy and speed of performance. CONCLUSIONS: The results suggest that children with IDDM do not have a pervasive deficit in speed of information processing, although more circumscribed deficits in processing speed are possible.

Adolescent↗