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911.
The performance of poor and normal sixth-grade readers was compared on an auditory short-term memory task in two studies. In the first study, the effects of distraction, list length, and speed of stimulus presentation were investigated to test the hypothesis that the performance of the poor readers is affected by deficits in selective attention. Group differences in performance, however, were obtained for both distraction and no-distraction conditions. The second experiment examined the hypothesis that group differences may reflect differences in the use of rehearsal. In the second experiment, half the reading-disabled children and half the controls were provided with rehearsal training prior to completing the same short-term memory task a second time. Rehearsal training resulted in improved performance relative to children who were not trained; however, there was no rehearsal training x reading group interaction. The poor readers continued to show deficits in performance relative to the performance of control children. The results of these two studies suggest that deficits observed for poor readers on short-term memory tasks may reflect processing difficulties in some area that precedes rehearsal and affects performance under both distraction and no-distraction conditions.The authors wish to express their thanks to the Sachem School District and Betty Gould, Nicholas Opinanate, and Guy Barber for their unlimited cooperation, and to John Neale for very helpful discussions of a number of issues in this paper.  相似文献   
912.
A sample of 2,453 grade school children were followed into young adulthood through record sources. Teacher interviews provided information about low-peer-status children that was assessed in relation to subsequent delinquency for both sexes and young adult criminality for males. A multivariate design evaluated the joint effects of social class, a measure of family disturbance, and childhood problem behavior factors as antecedents of delinquency. Childhood aggression emerged as the most prominent antecedent factor for males but not for females. Social class and family disturbance were associated with aggression but did not have significant direct effects on delinquency. Aggression was related to severity of delinquency. Dispositional status, reflecting severity, was the best indicator of which delinquent males would have adult criminal records. A causal model is presented.The study was supported by a grant from the Scottish Rite Schizophrenia Research Program, N.M.J., U.S.A. Portions of the study were presented at the Life History Research conference in Monterey, California, 1981. The authors wish to thank June White, Cindy Hanson, and Ned Worell for their help in conducting this research. Data for this research was originally gathered by Merrill Roff. Follow-up data were contributed by Ronald Peek, Donald Bamber, Charles Watson, Shiela Makie, William S. Ward, Edward S. Posey, Chris Hemlabs, and Harriet Barnes.  相似文献   
913.
914.
Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.  相似文献   
915.
Motor programme information as a separable memory unit   总被引:1,自引:0,他引:1  
Summary Two experiments produced further evidence for the claim that motor programme information may be considered as a separate memory unit, partially independent of other memory representations. In Experiment 1, it was shown that for the comparison of shared movement components in two actions such as turning the handle and stirring the ingredients, the activation of their motor programmes is required. This is demonstrated by the finding that the execution of the first action, which preactivates its motor programmes, leads to shorter reaction times than under control conditions in which the verbally described action is only spoken. In Experiment 2, it was further shown that the execution of the action does not in every case expedite the assessment of a connection between a prime item and a target item vis à vis verbal repetition, but only where the task requires the activation of motor programmes.  相似文献   
916.
Odor recognition: familiarity, identifiability, and encoding consistency   总被引:8,自引:0,他引:8  
The investigation examined the association between the perceived identity of odorous stimuli and the ability to recognize the previous occurrence of them. The stimuli comprised 20 relatively familiar odorous objects such as chocolate, leather, popcorn, and soy sauce. Participants rated the familiarity of the odors and sought to identify them. At various intervals up to 7 days after initial inspection, the participants sought to recognize the odors among sets of distractor odors that included such items as soap, cloves, pipe tobacco, and so on. The recognition response entailed a confidence rating as to whether or not an item had appeared in the original set. At the time of testing, the participants also sought to identify the stimuli again. The results upheld previous findings of excellent initial recognition memory for environmentally relevant odors and slow forgetting. The results also uncovered, for the first time, a strong association between recognition memory and identifiability, rated familiarity, and the ability to use an odor label consistently at inspection and subsequent testing. Encodability seems to enhance rather than to permit recognizability. Even items identified incorrectly or inconsistently were recognized at levels above chance.  相似文献   
917.
Representation of linear orders   总被引:1,自引:0,他引:1  
Two binary classification tasks were used to explore the associative structure of linear orders. In Experiment 1, college students classified English letters as targets or nontargets, the targets being consecutive letters of the alphabet. The time to reject nontargets was a decreasing function of the distance from the target set, suggesting response interference mediated by automatic associations from the target to the nontarget letters. The way in which this interference effect depended on the placement of the boundaries between the target and nontarget sets revealed the relative strengths of individual interletter associations. In Experiment 2, students were assigned novel linear orders composed of letterlike symbols and asked to classify pairs of symbols as being adjacent or nonadjacent in the assigned sequence. Reaction time was found to be a joint function of the distance between any pair of symbols and the relative positions of those symbols within the sequence. The effects of both distance and position decreased systematically over 6 days of practice with a particular order, beginning at a level typical of unfamiliar orders and converging on a level characteristic of familiar orders such as letters and digits. These results provide an empirical unification of two previously disparate sets of findings in the literature on linear orders, those concerning familiar and unfamiliar orders, and the systematic transition between the two patterns of results suggests the gradual integration of a new associative structure.  相似文献   
918.
Detection versus discrimination of visual orientation   总被引:4,自引:0,他引:4  
D Sagi  B Julesz 《Perception》1984,13(5):619-628
The role of focused attention in vision is examined. Recent theories of attention hypothesize that serial search by focal attention is required for discrimination between different combinations of features. Experiments are reported which show that the mixture of a few (less than five) horizontal and vertical line segments embedded in an aggregate of diagonal line segments can be rapidly counted (also called 'subitizing') by a parallel (preattentive) process, while the discrimination between horizontal and vertical orientation requires serial search by shifting focal attention to each line segment. Thus detecting and counting targets that differ in orientation can be done in parallel by a preattentive process, whereas knowing 'what' the orientation of a target is (horizontal or vertical, ie of a single conspicuous feature) requires a serial search by focal attention.  相似文献   
919.
Studies were made of rapid error correction movements in eight subjects performing a visually guided tracking task involving flexion-extension movements about the elbow. Subjects were required to minimize reaction times in this two-choice task. Errors in initial movement direction occurred in about 3% of the trials. Error correction times (time from initiation to reversal of movement in incorrect direction) ranged from 30-150 ms. The first sing of correction of the error movement was a suppression of the electromyographic (EMG) activity in the muscle producing the error movement. This suppression started as early as 20-40 ms after the initiation of the error-related EMG activity and as much as 50 ms before any overt sign of limb movement. The correction of the error movement was also accompanied by an increase in the drive to the muscle which moved the arm in the correct direction. This increased activity always occurred after the initiation of the error movement. it is concluded that the first step in the error correction, suppression of drive to the muscle producing the error movement, cannot be based on information from the moving limb. It is thus suggested that this earliest response to the error movement is based on central monitoring of the commands for movement.  相似文献   
920.
Sixteen stories were read to children at ages 4, 7, and 11 years and to college freshmen (n = 24 per age level) to investigate the effects of recency and specific story content on the development of moral reasoning. The stories consisted of either positive or negative intention and either positive or negative consequence in one of four situations: rule breaking, property damage, property damage with peer interaction, or injury to a person. At each age level, half of the subjects heard the stories with the intention first and the consequence second, and half heard them in the reverse order. Analyses confirmed that in general younger children judged on consequence, whereas older children utilized intention, and that on stories containing intentional injury to a person, the younger child took intention into account. Recency effects were evidenced for both the 4- and 7-year-olds. In the 4-year-old group, however, the recency effects failed to override the salience of negative consequence in contexts of positive intention and negative consequence. This suggests that preschool children may respond primarily to the negative aspect of the story, whether intention or consequence.  相似文献   
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