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121.
Parenting and family stress treatment outcomes in the MTA study were examined. Male and female (579), 7–9-year-old children with combined type Attention Deficit Hyperactivity Disorder (ADHD), were recruited at six sites around the United States and Canada, and randomly assigned to one of four groups: intensive, multi-faceted behavior therapy program alone (Beh); carefully titrated and monitored medication management strategy alone (MedMgt); a well-integrated combination of the two (Comb); or a community comparison group (CC). Treatment occurred over 14 months, and assessments were taken at baseline, 3, 9, and 14 months. Parenting behavior and family stress were assessed using parent-report and child-report inventories. Results showed that Beh alone, MedMgt alone, and Comb produced significantly greater decreases in a parent-rated measure of negative parenting, Negative/Ineffective Discipline, than did standard community treatment. The three MTA treatments did not differ significantly from each other on this domain. No differences were noted among the four groups on positive parenting or on family stress variables. Results are discussed in terms of the theoretical and empirically documented importance of negative parenting in the symptoms, comorbidities and long-term outcomes of ADHD.  相似文献   
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The measurement of “switch costs” is held to be of interest because, as is widely believed, they may reflect the control processes that are engaged when subjects switch between two (or more) competing tasks. [In task-switching experiments, the reaction time (RT) switch cost is typically measured as the difference in RT between switch and non-switch (repeat) trials.] In this report we focus on the RT switch costs that remain even after the subject has had some time to prepare for the shift of task, when the switch cost may be approximately asymptotic (so-called residual switch costs). Three experiments are presented. All three experiments used Stroop colour/word, and neutral stimuli. Participants performed the two tasks of word-reading and colour-naming in a regular, double alternation, using the “alternating runs” paradigm (R. D. Rogers & S. Monsell, 1995). The experiments were designed to test the hypothesis that RT switch costs depend on a form of proactive interference (PI) arising from the performance of a prior, competing task. A. Allport, E. A. Styles and S. Hsieh (1994) suggested that these PI effects resulted from “task-set inertia”, that is, the persisting activation-suppression of competing task-sets, or competing task-processing pathways. The results confirmed the existence of long-lasting PI from the competing task as a major contributor to switch costs. Non-switch trials, used as the baseline in the measurement of switch costs, were also shown to be strongly affected by similar PI effects. However, task-set inertia was not sufficient to account for these results. The results appeared inconsistent also with all other previous models of task switching. A new hypothesis to explain these between-task interference effects was developed, based on the stimulus-triggered retrieval of competing stimulus-response (S-R) associations, acquired (or strengthened) in earlier trials. Consistent with this retrieval hypothesis, switch costs were shown to depend primarily on the S-R characteristics of the preceding task (the task that was switched from) rather than the upcoming task. Further, the effects of the other, competing task were found to persist over many successive switching trials, affecting switch costs long after the stimulus overlap (and hence the principal S-R competition) between the current tasks had been removed. Switch costs were also found to be affected by recent, item-specific experience with a given stimulus, in either the same or the competing task. Finally, the results showed that switch costs were massively affected by the ratio of the number of prior trials, in response to the same stimuli, that had implemented either the currently intended or the competing S-R mappings. None of these effects are predicted by current models of residual switch costs, which appeal to the differences in control processes assumed to be engaged in switch versus non-switch trials. Received: 31 March 1999 / Accepted: 23 July 1999  相似文献   
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Elliott L  Orr L  Watson L  Jackson A 《Adolescence》2005,40(157):1-22
This paper reviews the international scientific evidence on the effectiveness of secondary prevention interventions for young drug users. The review provides insight into the effectiveness of interventions that have been evaluated using moderately strong research designs. Most of the studies included are from the United States of America. Some interventions are effective in reducing drug use and associated problems while others have no or mixed effect. Those successful in reducing drug use include behavior therapy, Minnesota 12-step programs, residential care, and general drug treatment. Those with either no effect or mixed effect include schools interventions. Involving parents and other agencies may enhance an intervention's effect. There is a lack of good quality studies outside the USA. Future interventions should focus on either low- or high-risk groups of young drug users. Future research should be conducted on a wider range of services for young people and include non-medical outcomes such as communication skills, schooling, employment, family relations, and economic costs.  相似文献   
126.
For both humans and animals, domain-general mechanisms are fallible but powerful tools for attaining evolutionary goals (e.g., resources) in uncertain, novel environments that were not recurrent features of the environment of evolutionary adaptedness. Domain-general mechanisms interact in complex ways with domain-specific, information-encapsulated modules, most importantly by manipulating information obtained from various modules in attempting to solve novel problems. Mechanisms of general intelligence, particularly the executive functions of working memory, underlie analogical reasoning as well as the decontextualization processes that are central to human thought. Although there is a variety of evolved, special purpose learning devices, learning is also characterized by domain-general mechanisms that are able to achieve evolutionary goals by making novel and serendipitous associations with environmental cues.  相似文献   
127.
Attitudes held with strong moral conviction (moral mandates) were predicted to have different interpersonal consequences than strong but nonmoral attitudes. After controlling for indices of attitude strength, the authors explored the unique effect of moral conviction on the degree that people preferred greater social (Studies 1 and 2) and physical (Study 3) distance from attitudinally dissimilar others and the effects of moral conviction on group interaction and decision making in attitudinally homogeneous versus heterogeneous groups (Study 4). Results supported the moral mandate hypothesis: Stronger moral conviction led to (a) greater preferred social and physical distance from attitudinally dissimilar others, (b) intolerance of attitudinally dissimilar others in both intimate (e.g., friend) and distant relationships (e.g., owner of a store one frequents), (c) lower levels of good will and cooperativeness in attitudinally heterogeneous groups, and (d) a greater inability to generate procedural solutions to resolve disagreements.  相似文献   
128.
The current study used ecological momentary assessment to test several tenets of the reserve capacity model (L.C. Gallo & K. A. Matthews, 2003). Women (N = 108) with varying socioeconomic status (SES) monitored positive and negative psychosocial experiences and emotions across 2 days. Measures of intrapsychic and social resources were aggregated to represent the reserve capacity available to manage stress. Lower SES was associated with less perceived control and positive affect and more social strain. Control and strain contributed to the association between SES and positive affect. Lower SES elicited greater positive but not negative emotional reactivity to psychosocial experiences. Women with low SES had fewer resources relative to those with higher SES, and resources contributed to the association between SES and daily experiences.  相似文献   
129.
Constraints and triggers: situational mechanics of gender in negotiation   总被引:1,自引:0,他引:1  
The authors propose 2 categories of situational moderators of gender in negotiation: situational ambiguity and gender triggers. Reducing the degree of situational ambiguity constrains the influence of gender on negotiation. Gender triggers prompt divergent behavioral responses as a function of gender. Field and lab studies (1 and 2) demonstrated that decreased ambiguity in the economic structure of a negotiation (structural ambiguity) reduces gender effects on negotiation performance. Study 3 showed that representation role (negotiating for self or other) functions as a gender trigger by producing a greater effect on female than male negotiation performance. Study 4 showed that decreased structural ambiguity constrains gender effects of representation role, suggesting that situational ambiguity and gender triggers work in interaction to moderate gender effects on negotiation performance.  相似文献   
130.
Key pecking by 3 pigeons was maintained by a multiple fixed-ratio 10, fixed-ratio 30, fixed-ratio 90 schedule of food presentation. Components differed with respect to amount of reinforcement, such that the unit price was 10 responses per 1-s access to food. Acute administration of morphine, l-methadone, and cocaine dose-dependently decreased overall response rates in each of the components. When a rate decreasing dose of morphine was administered daily, tolerance, as measured by an increase in the dose that reduced response rates to 50% of control (i.e., the ED50 value), developed in each of the components; however, the degree of tolerance was smallest in the fixed-ratio 90 component (i.e., the ED50 value increased the least). When the l-methadone dose-effect curve was redetermined during the chronic morphine phase, the degree of cross-tolerance conferred to l-methadone was similar across components, suggesting that behavioral variables may not influence the degree of cross-tolerance between opioids. During the chronic phase, the cocaine dose-effect curve shifted to the right for 2 pigeons and to the left for 1 pigeon, which is consistent with predictions based on the lack of pharmacological similarity between morphine and cocaine. When the morphine, l-methadone, and cocaine dose-effect curves were redetermined after chronic morphine administration ended, the morphine and l-methadone ED50s replicated those obtained prior to chronic morphine administration. The morphine data suggest that the fixed-ratio value (i.e., the absolute output) determines the degree of tolerance and not the unit price.  相似文献   
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