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71.
Using a two-stimulus reaction time paradigm, with two separate reward conditions (contingent and noncontingent), we compared slow wave brain potentials (ERPs) in 144 children with attention deficit disorder (ADD) and 30 normal control children. This article reviews the findings during the 900 msec visual warning stimulus. As we had expected, based on ERP work of Forth and Hare (1989) and Raine, Venables and Williams (1990), and on previous work from our own laboratory, the group differences were found in the negative slow wave portions of the ERP complex during the contingent reward condition but not during the noncontingent condition. Aggressive hyperactive subjects with attention deficit disorder (ADDHA) were discriminated from nonaggressive subjects (including control subjects) during the contingent reward condition in the following ways: (1) greater fronto-central negativity (640–900 msec slow wave) and (2) greater right parietal than left parietal negativity (430–750 msec slow wave). All ADD subgroups, when compared to control (CONTR) subjects, showed greater slow wave negativity (700–900 msec) at the midline occipital electrode site during the contingent reward condition. This could be explained in part as an IQ effect on ERPs reflecting the IQ difference between the ADD subgroups and the controls. These slow wave findings seem to relate to attentional problems of these children. They are discussed in terms of a psychobiological model of inhibition/disinhibition and appetitive activation.  相似文献   
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Book review     
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In response to new theoretical conceptualizations (Raven, 1992, 1993), an instrument was developed to measure 11 bases of power, the original 6 French and Raven (1959; Raven, 1965) bases of power, with 3 of these further differentiated: reward (personal, impersonal), coercion (personal. impersonal), legitimate (position, reciprocity, equity, dependence), expert, referent, and information. In Study 1, 317 American student respondents rated the likelihood that each of these power bases contributed to a supervisor successfully influencing a subordinate in a series of hypothetical situations. The internal consistency of the items which made up the 11 power bases proved adequate. Factor analysis found 7 factors and 2 categories of bases: harsh and soft. In Study 2, which used 101 Israeli health workers, the earlier findings were generally supported. In addition, job satisfaction was found to be positively related to the attribution of soft bases to the supervisor.  相似文献   
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FEMALE PARTNERS OF BISEXUAL MEN What They Don't Know Might Hurt Them   总被引:2,自引:0,他引:2  
Individual interviews with 350 behaviorally bisexual men aged 18–30 revealed that 71% of their female sexual partners and 59% of their steady female sexual partners in the past 6 months had not been aware of their homosexual activity. Rates of nondisclosure were higher for African-American than White men. Compared to nondisclosers, men who disclosed to all their female partners were less self-homophobic and perceived their friends, families, and neighbors as more accepting of their homosexual behavior. Compared to men who had disclosed, the nondisclosers had more female partners and used condoms less consistently with women.  相似文献   
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The system of behavior [B] consists of those transactional interrelationships between organism [O] and environment [E] that govern their commerce. The biological significance of such [O]-[E] interrelationships, their truing through learning, as well as those systems involved in the subordinate and superordinate regulation of behavior, are clear when life, itself, is seen as an emergent property of the [O]-[E] complex. In addition, a systems view of these hierarchically organized complexities suggests that they adaptively self-stabilize and self-organize, over time, as they participate in [L], the organism-environment complex. Such a transactional analysis of biobehavioral systems resonates well with the most basic axioms of Pavlov’s paradigm.  相似文献   
77.
Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.  相似文献   
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The present study assessed intellectual, academic, and emotional strengths and weaknesses for a group of Mexican-American children of migrant farm workers. In order to test the vulnerability hypothesis, the test profiles of these children were contrasted with those of two groups of black children with similar demographic makeup. The children of one group (Clinical Black) had been referred previously for a psychological consultation while the children of the other (Nonreferred Black) had not. Across dependent measures, between-groups contrasts tended to describe the scores of the Migrant children as similar to those of the Clinical Black children and significantly below those of the Nonreferred Black children. The findings suggested specific intellectual, academic, and emotional vulnerabilities of the Migrant children and demonstrated the need to develop ameliorative programs for these children.The authors wish to thank the staff of C & Y, University of Virginia Hospital, especially Ms. Deborah Johnson and Ms. Suzanne Canale, whose cooperation and assistance made this project possible.  相似文献   
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