The coordination of compensatory tracking and anticipatory timing tasks

Two experiments investigated the presence of a coordination factor in a task consisting of compensatory tracking and anticipatory timing components. The task (Intercept task) resembles a computer game in which a rocket must be aimed and fired to shoot an incoming missile. The studies were designed to determine if a coordinating ability exists above and beyond the abilities needed to perform the component tasks alone. We also investigated the nature of coordination abilities through correlations with other types of coordination tasks and measures of intelligence. Is coordination a general cognitive ability that contributes to performance in a wide range of coordination tasks, or is coordination ability task specific? Multiple regression analyses indicated the existence of a coordination ability in the Intercept task. This coordination ability, however, was shown to be unrelated to the coordination of visual and linguistic processing and to psychometric measures of intelligence as assessed by the Armed Services Vocational Aptitude Battery (ASVAB). Coordination of visual and linguistic processing correlated with a component of the ASVAB measuring perceptual speed. We conclude that, although the ability to integrate separate components of a complex task draws on a coordination ability, this ability is domain specific and thus varies depending on the nature of the component tasks.     

Sensitivity to event timing in regular and irregular sequences: Influences of musical skill

In two experiments, the performance of listeners with different amounts of musical training (high skill, low skill) was examined in a two-alternative forced choice time-detection task involving simple five-cycle acoustic sequences. In each of a series of trials, all listeners determined which of two pattern cycles contained a small time change. Sequence context was also varied (regular vs. irregular timing). In Experiment 1, in which context was manipulated as a between-subjects variable, high-skill listeners performed significantly better than low-skill listeners only with regular patterns. In Experiment 2, in which context was manipulated as a within-subjects variable, the only significant source of variance was pattern context: All listeners were better at detecting time changes in regular than in irregular patterns. The results are considered in light of several hypotheses, including the expectancy/contrast model (Jones & Boltz, 1989).     

Early stimulus processing in dysthymia and anhedonia.

Previous event-related brain potential (ERP) research has found that dysthymic subjects differ from control subjects during later stages of information processing. An important issue that emerges from this literature is whether differences found in these ERP components, typically associated with cognitive processing, can be attributed to earlier differences in basic perceptual processing. This study was undertaken to determine whether early processing deficits are apparent in dysthymic persons. Responses of dysthymics (n = 23) were compared with those of anhedonic (n = 15) and normal control (n = 17) subjects. ERPs were recorded while subjects heard tones at 55, 65, 75, 85, and 95 dB. Overall, N1-P1 and N1-P2 components of the ERP increased in a strong linear fashion as stimulus intensity increased. Dysthymics did exhibit a smaller N1-P2 response than normal subjects, which suggests the presence of difficulties in initial perceptual processing.     

The development of social networks from early to middle childhood: Gender differences and the relation to school competence

The purpose of this study was to examine gender differences in social network development from early to middle childhood and the relation of network characteristics to school competence. Maternal report of 75 children's kin, nonkin adult, and friendship networks were collected at 3, 6, and 9 years of age. Teacher ratings of school competence were obtained at 9 years. While children showed changes in their social networks over time, expected gender differences were not found in the extensive nature of the nonkin network. However, as expected, preference for same-sex friends was noted in early childhood and intensified with age into middle childhood. For girls, but not for boys, social network characteristics were related to teacher ratings of social competence in school.The preparation of this paper was made possible by the support of the William T. Grant Foundation.     

Parent perceptions and attributions for children's math achievement

From junior high school on, girls report lower estimations of their math ability and express more negative attitudes about math than do boys, despite equivalent performance in grades. Parents show this same sex-typed bias. This paper examines the role that attributions may play in explaining these sex differences in parents' perceptions of their children's math ability. Mothers and fathers of 48 junior high school boys and girls of high, average, and low math ability completed questionnaires about their perceptions of their child's ability and effort in math, and their causal attributions for their child's successful and unsuccessful math performances. Parents' math-related perceptions and attributions varied with their child's level of math ability and gender. Parents credited daughters with more effort than sons, and sons with more talent than daughters for successful math performances. These attributional patterns predicted sex-linked variations in parents' ratings of their child's effort and talent. No sex of child effects emerged for failure attributions; instead, lack of effort was seen as the most important, and lack of ability as the least important, cause of unsuccessful math performances for both boys and girls. Implications of these attributions for parents' influence on children's developing self-concept of math ability, future expectancies, and subsequent achievement behaviors are discussed.This paper is based on a master's thesis by the first author. This research was funded by grants to Jacquelynne S. Eccles from the following agencies: the Foundation for Child Development, the National Institute of Mental Health, and the National Institute of Child Health and Development.We wish to express our thanks to Linda Buford, Sandra Hamman, and Samuel D. Miller, who helped collect and code these data, and especially to the parents, students, and teachers in the Ann Arbor Public School district, whose cooperation made this project possible.     

The child's social network: Sex differences from three to six years

The social networks of 85 young children as they make the transition from a home-centered to a more school-centered existence is examined using longitudinal data. When the children were three and six years of age, their mothers completed a questionnaire of network structure; at six years both the child and mother independently reported the friends that the child would invite to a birthday party. The effects of age and sex of child on the number and daily contact with peers, adults, kin, nonkin, males, and females were found. As expected, as children reached formal school age they had increased contact with peers and decreased contact with kin, while adult contact remained fairly consistent over the three- to six-year age period. Sex differences were also apparent. As predicted, children as early as 3 years, and to an even greater extent at six years, showed more same-sex compared to opposite-sex peer contact. At six years both children and mothers reported more same- as compared to opposite-sex friends who would be invited by the child to a birthday party. The findings suggest how children's social networks, as shaped by their parents and themselves, provide a framework within which experience and interaction is structured to fit cultural norms.     

Visual working memory depends on attentional filtering

Working memory holds information actively being used in cognitive performance. Two important aspects of working memory are how many items it can hold, and how efficiently it can be used. Recently, Vogel and colleagues used event-related brain potentials to show that these two things are related. People who could remember more objects from a spatial array also more efficiently excluded irrelevant objects. The results raise important questions about what aspect of working memory is most fundamental.     

When do visual and verbal memories conflict? The importance of working-memory load and retrieval

Examinations of interference between verbal and visual materials in working memory have produced mixed results. If there is a central form of storage (e.g., the focus of attention; N. Cowan, 2001), then cross-domain interference should be obtained. The authors examined this question with a visual-array comparison task (S. J. Luck & E. K. Vogel, 1997) combined with various verbal memory load conditions. Interference between tasks occurred if there was explicit retrieval of the verbal load during maintenance of a visual array. The effect was localized in the maintenance period of the visual task and was not the result of articulation per se. Interference also occurred when especially large silent verbal and visual loads were held concurrently. These results suggest central storage along with code-specific passive storage.