Finger localization and reading ability in three groups of children ages three through twelve

Developmental norms for eight finger-localization (FL) tasks similar to those used by Lindgren are extended to include 140 children ages 3 through 12. The strength of the relationship between these scores and two specific reading tasks is explored. Regression analyses reveal statistically significant correlations between FL ability and the ability to match spoken with printed words, as well as between FL scores and scores for silent reading and retelling of a paragraph. Three groups of children are used: children with normal language, those with dysphasia, and those with language impairments other than dysphasia. Performance scores of these three groups on other language tasks are compared.     

Semantic memory verification of binary statements by children at three academic levels

Ninety-six binary statements were administered to 120 children randomly selected from three academic levels. The children were to respond TRUE or FALSE to each statement. Error count and latency for correct responses were used as measures of performance. The Constituent Comparison Model (Carpenter, P., & Just, M. A., Psychological Review, 1975, 82, 45–73), which postulates that verification latency will increase linearly with a linear increase in the number of hypothesized constituent comparisons, accounts quite well for the results obtained in this study. Furthermore, the results suggest an increasing efficiency in semantic memory verification across the three academic levels as reflected by a decrease in variability of performance, a decrease in the time required to read and encode sentences, and a decrease in the time required per constituent comparison.     

Individual differences in process outcomes for verbal analogy and classification solution

Adult performance on verbal analogy and classification problems was assessed in terms of the outcomes of process execution. Measures were obtained for the accuracy of stem processing and subsequent alternative processing. The process-outcome measures obtained within each task accounted for overall performance scores and were differentially related to ability. This was shown by ability differences in the models accounting for subjects' overall accuracy and in the correlational patterns. Analogy and classification problem forms differed in the measures most important for predicting individual differences. Specifically, measures of alternative processing were more important in classification than analogy solution and application was shown to be important for analogy solution. In addition, common process-outcome measures showed the highest correlations across problem forms, consistent with the assumption that both induction tasks tap similar psychological processes. The results are discussed with respect to previous studies assessing commonality and individual differences among children in process-outcomes.     

Distortions in memory for maps

Evidence is presented for systematic errors in memory for real and artificial maps, local environments, and visual forms. These errors are attributed to two heuristics that are derived from principles of perceptual organization. Maps of countries or localities are conceived of as figures in backgrounds. Remembering the absolute location of figures is difficult, and is facilitated by remembering locations relative to other figures and/or relative to the natural directions of the figure. In alignment, figures are lined up relative to one another, a phenomenon related to perceptual grouping by proximity. In rotation, the natural axes induced by a figure converge with frame axes (north-south, east-west, or horizontal, vertical), a phenomenon related to perceptual organization by common fate. Heuristic-induced errors occur in a variety of tasks, and even when subjects are explicitly forewarned. These heuristics may be invoked in forming representations as well as in inference, and function analogously to syntax in locating smaller elements in larger units.     

A heuristic method for the comparison of related structures

By extending a technique for testing the difference between two dependent correlations developed by Wolfe, a strategy is proposed in a more general matrix context for evaluating a variety of data analysis schemes that are supposed to clarify the structure underlying a set of proximity measures. In the applications considered, a data analysis scheme is assumed to reconstruct in matrix form the given data set (represented as a proximity matrix) based on some specific model or procedure. Thus, an evaluation of the adequacy of reconstruction can be developed by comparing matrices, one containing the original proximities and the second containing the reconstructed values. Possible applications in multidimensional scaling, clustering, and related contexts are emphasized using four broad categories: (a) Given two different reconstructions based on a single data set, does either represent the data significantly better than the other? (b) Given two reconstructions based on a single data set using two different procedures (or possibly, two distinct data sets and a common method), is either reconstruction significantly closer to a particular theoretical structure that is assumed to underlie the data (where the latter is also represented in matrix form)? (c) Given two theoretical structures and one reconstruction based on a single data set, does either represent the reconstruction better than the other? (d) Given a single reconstruction based on one data set, is the information present in the data accounted for satisfactorily by the reconstruction? In all cases, these tasks can be approached by a nonparametric procedure that assesses the similarity in pattern between two appropriately defined matrices. The latter are obtained from the original data, the reconstructions, and/or the theoretical structures. Finally, two numerical examples are given to illustrate the more general discussion.     

Menstrual cycle effects on task performance examined in the context of stress research

The study examined the effects of degree of paramenstrual distress, signal frequency, task load and time on task on psychomotor performance across the menstrual cycle. Simple reaction time, choice reaction time and pursuit tracking were the tasks employed, and performance was assessed using the metrics of mean level, variability, and errors of omission and commission. The results showed performance as a function of menstrual cycle phase and paramenstrual distress to be highly task and metric specific, a finding typical of stressor variables: pursuit tracking was affected by phase, with mean performance at its worst premenstrually; choice reaction time was dependent on a complex interaction of experimental variables and measurement metrics; simple reaction time showed no significant effects. Patterns of attention allocation in a time-sharing situation combining both pursuit tracking and choice reaction time components were also investigated. Trends here indicated relatively better performance both menstrually and intermenstrually as components increased in signal/response frequency, with a corresponding deterioration premenstrually. Overall performance capacity appeared to be greatest at menstruation, and the degree of attentional selectivity was least. High distress women performed better on low frequency components, whereas asymptomatic women did better at higher signal rates.     

Children's judgments of numerical quantity: A new view of early quantification

Three experiments investigated the role of length, density, and number dimensions in children's numerosity judgments of linear arrays of beads. The number dimension is physically defined by a length × density rule. Judgments based, even in part, on the number dimension would show signs of a length × density rule. Experiment 1 examined numerosity judgments of large arrays. Results showed that judgments by 3- and 4-year-olds obeyed a length + density rule, providing cogent evidence for a general adding strategy in young children's judgments of quantity. The physical length × density rule emerged gradually with increasing age. Experiment 2 showed that numerosity judgments of small arrays by 3- and 4-year-olds obeyed a length × density rule, indicating response to the number dimension. This result was expected and thereby validated the linearity of the response scale at the youngest ages. Experiment 3 verified the integration rules for individual 3- and 4-year-olds. The integration rules were interpreted in terms of Piaget's stages of the development of quantification. No evidence for Piaget's initial stage was found. This leads to a new view of early quantification which grants young children the ability to integrate stimulus dimensions.     

VOT discrimination by four to six and a half month old infants from Spanish environments.

Thirty 4–6.5 mo-old-infants from monolingual Spanish speaking homes were tested for discrimination of bilabial stop consonants differing in VOT. Discrimination was determined by the habituation and dishabituation of the orienting reflex as indexed by cardiac deceleration. Subjects were placed in one of three groups of ten subjects each. The three groups were used to determine whether bilabial stops with VOT values of ?60 and ?20 msec, ?20 and +20 msec or +20 and +60 msec could be discriminated. Subjects were presented eight trial blocks of ten repetitions of a CV syllable; these eight trial blocks were followed by two trial blocks of ten repetitions of a different CV syllable. The only difference between the CV syllables presented during the first eight and the last two trial blocks was the VOT value of the bilabial stop consonants. Subjects in the ?20 and +20 msec group showed no signs of being able to discriminate these stimuli while the subjects in the ?60 and ?20 msec group and the +20 and +60 msec group did. These results correspond to those reported for infants from English speaking families but do not correspond to those reported for Spanish speaking adults. Thus, the failure to find evidence of discrimination in the ?20 and +20 msec group suggests that experience has little effect in determining bilabial stop phonetic categories in 4–6.5 mo-old infants.