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991.
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   
992.
Twenty hyperactive emotionally disturbed children (6–11 years) and a matched sample of nonhyperactive emotionally disturbed children were selected from the population of a therapeutic day treatment facility on the basis of teacher ratings. They were administered the Matching Familiar Figures Test-20 and were rated on several scales of impulsivity and/or hyperactivity. Each subject was required to perform on the Delay Task of the Gordon Diagnostic System, which required them to inhibit behavioral responding on a temporally based schedule (DRL-6) in order to win points. Children classified as hyperactive, whether by one or more criteria, were relatively unable to refrain from emitting a high number of nonreinforced responses. Moreover, these performance differences persisted regardless of age or IQ and were stable over the 8 minutes required to complete the test.The authors gratefully acknowledge the efforts of the following members of the Institute of Clinical Psychology, University of Virginia: Richard Abidin, Ann Loper, Ronald Reeve, and Sherry Kraft. Data analyses were conducted using STATMANAGER, Hayden Software Company, copyright 1983.  相似文献   
993.
The empirical research pertaining to the effectiveness of telephone counseling and referral systems personnel was critically reviewed. The assessment was organized according to several evaluation strategies that researchers have utilized to evaluate effectiveness. These strategies included, for example, client self-reports, client "shows" versus "no-shows" following referral, data pertaining to suicide rates, counselor ratings of personal effectiveness, and phone workers' ability to offer empathy to clients. It was concluded that discussions of effectiveness should be constrained by a careful consideration of the specific index of efficacy chosen by investigators as well as methodological issues associated with current research in this area. There is reason to believe that the availability of telephone crisis services may be related to reduced suicide rates among young white females. Also, there is a significant need to empirically associate counseling technique and indices of effectiveness with substantive measures of client outcome in future research. Additional topics reviewed include the probable differential effectiveness of lay workers with various presenting problems of clients, and the role that training and maturity seem to play in successful interventions. Guidelines for the use of evaluation techniques which coincide with service goals are also offered.  相似文献   
994.
995.
996.
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   
997.
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   
998.
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   
999.
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   
1000.
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   
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