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51.
We investigated the effects of background anger, provocation, and methylphenidate on emotional, physiological, and behavioral responding in children with attentiondeficit hyperactivity disorder (ADHD) with and without concurrent aggression. Our study revealed that ADHD boys showed more emotional and physiological distress when exposed to an interaction in which an administrator chastised each boy's favorite counselor, compared to a friendly interaction between the two adults. The background anger manipulation did not affect the aggressive behavior of the boys against an opponent in an aggressive game. High-aggressive (HA) ADHD boys were more likely to respond to provocation with aggression than low-aggressive (LA) ADHD boys, but only LA boys showed increased physiological reactivity with increasing provocation. Methylphenidate resulted in increased heart rates under all conditions and did not interact with any of the other findings.This project was conducted while the first author had the support of National Institute of Alcohol Abuse and Alcoholism grant AA 06267.The authors wish to thank the staff members of the 1987 Summer Day Treatment Program who assisted in conducting this project. The authors also express their appreciation to Karen Guthrie for coordinating the medication assessment and to Hart Blanton for computer programming.  相似文献   
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Recruiting help from mentors and other potential helpers is a promising strategy for helping disadvantaged and minority youths meet their personal and educational goals. Three African-American high school seniors participated in a project designed to evaluate the effectiveness of training procedures that would allow them to ask for help in attaining educational and other personal goals. A behavioral training procedure that included instructional materials, role-play practice, praise, and feedback was used. Targeted skills included goal setting and 30 responses involved in the process of meeting with a potential helper. Role-play situations were used to evaluate participants' help-recruiting skills before and after training. Participants increased their help-recruiting skills from an average of 38% during baseline, to an average of 75% after training. Self-reported measures of goal attainment suggested that the students benefited from the training. Implications for mentoring programs designed to increase minority students' opportunities to reach educational goals were discussed.  相似文献   
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A within-subject comparison was made of the effects of methylphenidate (Ritalin) and response cost in reducing the off-task behavior of two boys, 7 and 8 years of age, who had been diagnosed as having an attentional deficit disorder with hyperactivity. Several dosages of Ritalin (5 to 20 mg/day) were evaluated with the results indicating varying effects of the drug for both children. Response cost (with free-time as the reinforcer) was superior to Ritalin in raising levels of on-task behavior and in improving academic performance.  相似文献   
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The ‘skewness’ of a distribution, a poorly-defined term, is conventionally deemed to be invariant under linear transformations. A comparison is made of three criteria of it: the sign of odd central moments; the several relationships of the mean, the median and the mode; and asymmetry proper which is the set of ratios of the probability densities of all pairs of points equidistant above and below some arbitrary point, usually the principal mode. Some useful general relationships are discussed. The skeness of convolutions is briefly discussed. A class of distributions is identified for which the skewness of the minimum ofk competing processes is independent ofk. It has importance in the parametric study of survivorship.  相似文献   
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It was hypothesized that being a boy or a girl becomes more salient in a child's self-concept to the extent the other sex numerically predominates in the child's household. This prediction was based upon an information-processing, distinctiveness postulate that a person contemplating a complex stimulus (such as the self) selectively notices and encodes its more distinctive, information-rich aspects. The spontaneous self-concept elicited by nondirective “Tell us about yourself” interviews of 560 school children were scored for spontaneous mention of one's gender. As predicted, boys spontaneously mentioned their maleness more often when they came from households where females were in the majority; girls mentioned their femaleness more often when from households with male majorities; boys mentioned their maleness more often when from father-absent than from father-present homes. Incidental findings are that gender is more salient in the negation self-concept (“Tell us what you are not”) than in the affirmation self-concept (“Tell us about yourself”) especially for girls and that gender becomes increasingly salient as the child grows older.  相似文献   
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Summary When two briefly exposed, spatially overlapping visual fields are presented dichoptically, the identifiability of the first field is a J-shaped function of the interval separating their onsets. Three distinct sources of central masking are inferred from the selective influence of variables at different onset asynchronies. In integration through common synthesis, two fields presented at or near simultaneous onset yield one iconic representation. The distinctiveness of this source is inferred from the selective influence of eye dominance at and near simultaneous onset. At longer onset asynchronies, the selective influence of variables such as mask contrast and degree of contour overlap imply a second source of masking. This source was identified with the inhibition of sustained channels by transient channels reported elsewhere. Interchannel inhibition is proposed to affect the fidelity of the iconic representation, but here the imprecision is due to loss of form-relevant information on the first field. At yet longer onset asynchronies, where the fields are phenomenally separate, a third set of variables (e.g., words vs. nonwords and left vs. right visual fields) show their influence. These effects are taken as evidence of a replacement principle: the iconic representation of the second field directs attention from that of the first field. Here, first-field identifiability is constrained by time rather than by impoverished data.In a final series of experiments, central three-field interactions are demonstrated. A field, inserted into the temporal gap between two fields, is perceptually impaired even though it is separated from the first and third fields by intervals at which, individually, neither field is an effective mask. This second-field depression is accompanied by a first-field enhancement. The three sources of central masking are hard pressed to account for the three-field effects.  相似文献   
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In Experiment 1 two training procedures were used to teach four-year-olds to conserve. Verbal rule instruction consisted of providing verbal rules and demonstrations of the operations referred to by the rules. Feedback consisted of providing verbal feedback contingent upon the children's responses. One week after training on conservation of number and length the children were given a posttest which included tests of conservation of number, length, and mass. Children who were given verbal rule instruction conserved significantly more on the number and length posttest problems than children who were not. However, this learning did not transfer to the mass problems, possibly because mass is not naturally acquired until some time after conservation of number and length. The feedback training procedure had no effect on conservation performance. In Experiment 2, the verbal rule instruction procedure was used to train four-year-olds on conservation of length and mass. One week after training the children were tested on both conservation of number, which is typically acquired before length and mass, and conservation of weight, which is typically acquired after length and mass, as well as on conservation of length and mass. Children who were given training conserved more on all four types of problems than children in the control group.  相似文献   
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