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81.
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.
A stimulus leads to a cortical response (i.e., evoked potential [EP]) which may be recorded from electrodes attached to the scalp. However, background cortical activity, considered as noise (n), is typically of equal or greater magnitude than the response, which is considered as signal (s). This situation leads to the masking of the presence of the electrocortical signal. Two methods are described which enable the enhancement of the signal with respect to the noise. The first method outlined is time-domain averaging. Its relation to Fourier averaging is also presented. Time averaging can lead to an enhancement of the signal with respect to the noise, known as the signal-to-noise ratio (SNR), by a factor of root N; N being the number of trials recorded. However, latency variability (i.e., jitter) present in the signal leads to a decrement in this maximal potential enhancement. The second technique is an adaptive filter method of averaged cross-correlations, developed by Woody (1967), which deals with the variable latency problem. The development of a latency corrected average developed by McGillem and Aunon (1977) is also presented. The final section describes methods for data handling once the electrocortical signal has been enhanced. It is then necessary to describe the EP quantitatively. Principal Components Analysis (PCA) allows for the quantitative compact representation of the evoked potential waveform. The method also allows for the testing of the effects of explanatory variables on the EP.  相似文献   
83.
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   
84.
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   
85.
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   
86.
Three experiments were designed to investigate the influence of initial recall on memory by assessing delayed recall after different immediate cued-recall tests. In all experiments, subjects performed semantic and phonemic encoding tasks on a word list. The subjects then received a cued-recall test that cued the target using the same word as the context word in the encoding task, a test that cued the target with a word from the same level at which the target was encoded, a test that cued the target with a cue from a different level at which the target was encoded, or no immediate-recall test. One day later, the subjects performed a final cued-recall test in which the type of cue (semantic or phonemic) was varied. Consistently, delayed recall was facilitated primarily when the cue on the immediate test was from the same level as the cue on the delayed test. This pattern of facilitation suggests that immediate cued-recall produces an elaboration of an existing memory representation that is closely tied to the type of cue used on the immediate test.  相似文献   
87.
Research conducted primarily in the United States suggests that the combination of Type A behaviour, high instrumentality, and low expressiveness may place individuals at relatively high risk for coronary-artery and heart disease. The present research investigates the trans-societal generalizability of the structure, reliability, relationships among, and distributional characteristics of these measures for 117 college students in Athens, Greece. As hypothesized, the Greek students were significantly less instrumental and less expressive than the American students, and scored significantly higher on the measure of Type A. Although there were significant mean differences between these samples, the results suggest that many of the interscale relationships are comparable, supporting an etic (universal) interpretation of the findings. Nevertheless, the results suggested several emic (unique) characteristics of these measures and their interrelationships.  相似文献   
88.
This study tests the hypothesis that social anxiety and fear of bodily sensations are associated with the development of agoraphobic avoidance behavior in panic disorder patients. Twenty patients with panic disorder were compared to 20 patients with panic disorder with agoraphobia, matched by sex and duration of disorder. The two groups did not differ on measures of fear and frequency of assertive social responses. However, the agoraphobics scored higher on measures of interpersonal sensitivity, depression, feelings of inadequacy, and hostility. They also reported higher fear of bodily sensations. Although definitive conclusions need to be postponed until prospective studies have been conducted, there is evidence suggesting that the development of agoraphobia in panic patients is associated with hypersensitivity to bodily sensations and interpersonal situations.This research was supported by Grant 560-268-009 of the Dutch Organization for Scientific Research.  相似文献   
89.
It was a coincidence that I was asked to talk about resistance at Ground Rounds at the University of Texas, Department of Psychiatry, on the tenth anniversary of mailing the first version of Death of Resistance to a journal in 1979. Although the paper was subsequently rejected 17 times and revised six times, it was eventually published inFamily Process (de Shazer, 1984). I still insist that the concept of resistance was a bad idea for therapists to have in their heads.This paper was presented April 14, 1989, at Ground Rounds, University of Texas, Southwest Medical Center, Department of Psychiatry, Dallas, Texas.  相似文献   
90.
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