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131.
The present study was designed to examine the role that attentional problems may play in accounting for difficulties in story comprehension experienced by children with ADHD. A secondary task methodology was used to examine whether or not online variations in cognitive engagement with a televised story were related to the continuity of central or incidental information. Twenty-two 9- to 11 -year-old boys with ADHD and 36 of their nonreferred peers watched a television program and responded to auditory probes presented at preselected points during continuous sequences of central or incidental information. The reaction times to the probes for nonreferred boys showed the expected linear increase in cognitive engagement (i.e., the RTs increased) as central, plot-relevant sequences continued. In contrast, boys with ADHD showed the expected increase in RTs relatively late in the central sequences. The results were discussed in terms of how delays in engaging with central information may contribute to the academic difficulties experienced by boys with ADHD. 相似文献
132.
Spatial coherence does not affect contrast discrimination for multiple Gabor stimuli 总被引:1,自引:0,他引:1
Gestalt grouping rules imply a process or mechanism for grouping together local features of an object into a perceptual whole. Several psychophysical experiments have been interpreted as evidence for constrained interactions between nearby spatial filter elements and this has led to the hypothesis that element linking might be mediated by these interactions. A common tacit assumption is that these interactions result in response modulation which disturbs a local contrast code. We addressed this possibility by performing contrast discrimination experiments using two-dimensional arrays of multiple Gabor patches arranged either (i) vertically, (ii) in circles (coherent conditions), or (iii) randomly (incoherent condition), as well as for a single Gabor patch. In each condition, contrast increments were applied to either the entire test stimulus (experiment 1) or a single patch whose position was cued (experiment 2). In experiment 3, the texture stimuli were reduced to a single contour by displaying only the central vertical strip. Performance was better for the multiple-patch conditions than for the single-patch condition, but whether the multiple-patch stimulus was coherent or not had no systematic effect on the results in any of the experiments. We conclude that constrained local interactions do not interfere with a local contrast code for our suprathreshold stimuli, suggesting that, in general, this is not the way in which element linking is achieved. The possibility that interactions are involved in enhancing the detectability of contour elements at threshold remains unchallenged by our experiments. 相似文献
133.
Two experiments investigated the effects of different types of movement responses on coincidence timing skill. The view was taken that the sensory-motor integration of the movement responses would be reflected in the accuracy and consistency of anticipation timing. A Bassin anticipation timer provided a light stimulus velocity of 3 mph for both experiments and the movements studied included a simple key press using a finger, an arm movement to a key press, and whole body movements culminating with a kick or step to a target. The experiments were modelled closely on the seminal study by Grose (1967). The results of Exp. 1 supported our prediction by demonstrating superiority of the finger task over the two larger movements for all measures of coincidence timing ability. The purpose of Exp. 2 was to compare the slightly different versions of the whole body task-that used in the first experiment and that used by Grose (1967). The results confirmed the close similarity of the two movement tasks and re-affirmed the results of Exp. 1. Exp. 2 also investigated sex effects on coincidence timing ability and, in contrast to previous evidence indicating that females perform with less accuracy and consistency than do males, no significant differences were found. Analysis of practice effects showed that, although there were no significant improvements over trial blocks in Exp. 1, there were significant improvements in Exp. 2. Comparisons with other research suggests that repeated practice in solving a coincident timing problem using whole body movements can lead to improved performance. In general, the findings are consistent with the constructs of action theory and emphasize the roles perceptual and movement variables have in defining situational constraints. Also, findings indicate that proficiency in coincidence anticipation appears to be influenced by the planning and organisation required for movement execution. 相似文献
134.
Michael Williams 《Philosophical Studies》2001,103(3):341-342
Volume Contents
Contents Volume 103 2001 相似文献135.
Three experiments investigated memory performance in the retrieval practice paradigm (Anderson, Bjork, & Bjork, 1994; Anderson & Spellman, 1995). This paradigm produces a retrieval-induced forgetting effect, wherein practicing some members of a studied category decreases the recall of other members of that category relative to a baseline. Our findings indicate that the retrieval-induced forgetting effect is replicable but that previous findings supporting an inhibitory account of this phenomenon may not be. 相似文献
136.
137.
Previous studies have implicated depression, self-defeating behaviors, and self-destructive behaviors in suicide ideation. The present research directly compared these three concepts as predictors of both males' (n = 51) and females' (n = 78) suicide ideation. Analysis confirmed sex differences, with depression and self-defeating behaviors predicting females' suicide ideation, and self-destructive behaviors predicting males' suicide ideation. These results suggest that suicide may be related to these subtle yet relevant factors which may not be easily detected by mental health workers. 相似文献
138.
Children's artistic responses to musical intervals 总被引:4,自引:0,他引:4
In one experiment, White South African boys drew pictures in response to four musical intervals. In the second, the subjects were of both sexes and drawn from White, urban Black, and rural Black populations. Six intervals were used. Drawing content was similar cross-culturally. Consonances were perceived as generally positive; dissonances, generally negative. There was also an activity dimension. Children in a lower grade drew more concrete pictures than did those in a higher grade, regardless of age. Even young listeners were fairly consistent in their responses. This suggests that perception of musical meaning is a universal rather than culturally based phenomenon. 相似文献
139.
Racism as a stressor for African Americans. A biopsychosocial model. 总被引:30,自引:0,他引:30
Various authors have noted that interethnic group and intraethnic group racism are significant stressors for many African Americans. As such, intergroup and intragroup racism may play a role in the high rates of morbidity and mortality in this population. Yet, although scientific examinations of the effects of stress have proliferated, few researchers have explored the psychological, social, and physiological effects of perceived racism among African Americans. The purpose of this article was to outline a biopsychosocial model for perceived racism as a guide for future research. The first section of this article provides a brief overview of how racism has been conceptualized in the scientific literature. The second section reviews research exploring the existence of intergroup and intragroup racism. A contextual model for systematic studies of the biopsychosocial effects of perceived racism is then presented, along with recommendations for future research. 相似文献
140.
Williams and Best's (1982, 1990a) cross-culturalgender stereotype data from 25 countries, previouslyanalyzed in terms of affective meanings, ego states, andpsychological needs, were re-analyzed in terms of the Five Factor Model (FFM) of personality.In each country, participants were approximately 100university students, equally divided by gender. Withresults averaged across all countries, it was found that the pancultural male stereotype was higherthan the pancultural female stereotype on Extraversion,Conscientiousness, Emotional Stability, and Openness toExperience while the pancultural female stereotype was higher on Agreeableness. Re-analysis of thestereotype data from Japan and Pakistan, which had beenfound relatively atypical in previous analyses, revealedFFM profiles generally similar to the pancultural profiles. The evaluative nature of each factoris discussed and related to the stereotypes associalization models. 相似文献