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81.
Rolf Loeber Ph.D. Stephanie M. Green M.A. Benjamin B. Lahey Ph.D. Mary Anne G. Christ M.A. Paul J. Frick Ph.D. 《Journal of child and family studies》1992,1(1):21-41
Retrospective and prospective reports of the onset of disruptive child behaviors were analyzed in a sample of clinic-referred boys. The younger boys (ages 7–9 years), compared with the older boys (ages 10–12 years), showed the highest level of disruptive behavior and, judging from mothers' reports, had the fastest progression of onsets from less serious to more serious problem behaviors. Despite some overlap, developmental sequences in problem behavior within the domains of hyperactivity/inattention, oppositional behavior, and conduct problems were similar across the two age groups. This was also the case for developmental sequences of overt or confrontive problem behaviors and covert or concealing conduct problems. Sequences of the onset of oppositional behavior and conduct problems were validated through prospective data, based on the information from mothers, teachers, and boys themselves. The implications of the findings are discussed for the formulation of developmental pathways of behavior and the analysis of causal factors. 相似文献
82.
Jonathan Grainger J. Kevin O’Regan Arthur M. Jacobs Juan Segui 《Attention, perception & psychophysics》1992,51(1):49-56
Two experiments are described that measured lexical decision latencies and errors to five-letter French words with a single higher frequency orthographic neighbor and control words with no higher frequency neighbors. The higher frequency neighbor differed from the stimulus word by either the second letter (e.g.,astre-autre) or the fourth letter (chope-chose). Neighborhood frequency effects were found to interact with this factor, and significant interference was observed only tochope-type words. The effects of neighborhood frequency were also found to interact with the position of initial fixation in the stimulus word (either the second letter or the fourth letter). Interference was greatly reduced when the initial fixation was on the critical disambiguating letter (i.e., the letterp inchope). Moreover, word recognition was improved when subjects initially fixated the second letter relative to when they initially fixated the fourth letter of a five-letter word, but this second-letter advantage practically disappeared when the stimulus differed from a more frequent word by its fourth letter. The results are interpreted in terms of the interaction between visual and lexical factors in visual word recognition. 相似文献
83.
This paper studies a class of infinite-valued predicate logics. A sufficient condition for axiomatizability of logics from that class is given.To the memory of Jerzy Supecki 相似文献
84.
Working in the fragment of Martin-Löfs extensional type theory [12] which has products (but not sums) of dependent types, we consider two additional assumptions: firstly, that there are (strong) equality types; and secondly, that there is a type which is universal in the sense that terms of that type name all types, up to isomorphism. For such a type theory, we give a version of Russell's paradox showing that each type possesses a closed term and (hence) that all terms of each type are provably equal. We consider the kind of category theoretic structure which corresponds to this kind of type theory and obtain a categorical version of the paradox. A special case of this result is the degeneracy of a locally cartesian closed category with a morphism which is generic in the sense that every other morphism in the category can be obtained from it via pullback.The financial support of the Royal Society in London is gratefully acknowledged. 相似文献
85.
Context effects in stroop-like word and picture processing 总被引:7,自引:0,他引:7
Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color-color, picture-picture, and word-word stimuli instead of the usual modally mixed color-word or picture-word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test. 相似文献
86.
Two experiments were conducted to examine the hypothesized differential effectiveness of two attentional focusing strategies in pain perception. In the first experiment, subjects (72 male college students) rated their levels of pain after being exposed to either low- or high-intensity pressure stimulation for 75 s. Subjects were instructed to use either an external or internal focus of attention during the pain induction. Results revealed that external focusing was more effective for coping than internal focusing across both levels of stimulus intensity. The second experiment was a replication of the first, and featured bolstered internal focusing and stimulus intensity manipulations. Results showed that high-intensity stimulation produced higher pain ratings than did low-intensity stimulation for subjects in the internal focusing conditions, but not for those in the external focusing conditions. The findings support the power of distraction strategies for dealing with short-term pain with a rapid onset. Theoretical implications are discussed.The authors thank Darwyn E. Linder and Daniel M. Landers for their help in development of this research. The authors are also indebted to Sarah Colley, Jona Davis, Nanci Neuberger, and Rebecca Roberts for their assistance in data collection. 相似文献
87.
Paul R. Rosenbaum 《Psychometrika》1989,54(4):625-633
Established results on latent variable models are applied to the study of the validity of a psychological test. When the test predicts a criterion by measuring a unidimensional latent construct, not only must the total score predict the criterion, but the joint distribution of criterion scores and item responses must exhibit a certain pattern. The presence of this population pattern may be tested with sample data using the stratified Wilcoxon rank sum test. Often, criterion information is available only for selected examinees, for instance, those who are admitted or hired. Three cases are discussed: (i) selection at random, (ii) selection based on the current test, and (iii) selection based on other measures of the latent construct. Discriminant validity is also discussed.This work was supported in part by Grant SES-87-01890 from the Measurement Methods and Data Improvement Program of the U.S. National Science Foundation. 相似文献
88.
Spatial frequencies and the cerebral hemispheres: contrast sensitivity, visible persistence, and letter classification 总被引:1,自引:0,他引:1
The hypothesis that the two cerebral hemispheres are specialized for processing different visual spatial frequencies was investigated in three experiments. No differences between the left and right visual fields were found for: (1) contrast-sensitivity functions measured binocularly with vertical gratings ranging from 0.5 to 12 cycles per degree (cpd); (2) visible persistence durations for 1- and 10-cpd gratings measured with a stimulus alternation method; and (3) accuracy (d') and reaction times to correctly identify digitally filtered letters as targets (L or H) or nontargets (T or F). One significant difference, however, was found: In Experiment 3, a higher decision criterion (beta) was used when filtered letters were identified in the right visual field than when they were identified in the left. The letters were filtered with annular, 1-octave band-pass filters with center spatial frequencies of 1, 2, 4, 8, and 16 cpd. Combining four center frequencies with three letter sizes (0.5 degrees, 1 degree, and 2 degrees high) made some stimuli equivalent in distal spatial frequency (cycles per object) and some equivalent in proximal spatial frequency (cycles per degree). The effective stimulus in the third experiment seemed to be proximal spatial frequency (cycles per degree) not distal (cycles per object). We conclude that each cerebral hemisphere processes visual spatial frequency information with equal accuracy but that different decision rules are used. 相似文献
89.
Mark D. Rapport Sheila O. Quinn George J. DuPaul Eugene P. Quinn Kevin L. Kelly 《Journal of abnormal child psychology》1989,17(6):669-689
This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic. 相似文献
90.
Semantic priming in a lexical decision task was investigated with concurrent pretarget and posttarget primes. The posttarget prime also served as a pattern mask of the lexical decision target. Forward priming is defined as the presence of a semantically related pretarget prime and an unrelated posttarget prime. Backward priming is defined as the presence of a semantically related posttarget prime and an unrelated pretarget prime. Forward and backward priming were compared both when the nonword foils were "legal" and when they were "illegal" with respect to English orthography. Predictions were derived for two general approaches to word recognition: spreading-activation and expectancy-set theories. Both approaches assume that word representations occupy distinct, nonoverlapping locations in memory. Backward-prime facilitation was equivalent to forward-prime facilitation when nonword foils were illegal; however, backward-prime facilitation was not significant when nonword foils were legal. These results challenge both approaches. The proposed solution uses semantic-space (distributed) representations that are functionally unitized by a resonant matching (verification) process. 相似文献