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Previous research demonstrates that older adults are poor at dual tasking, but there is less agreement on whether their decrement is worse than that predicted from single-task performance. This study investigated whether task domain moderates dual-task costs in old age. In two experiments, young and older adults retrieved either previously learned associates (episodic retrieval) or overlearned category members (semantic retrieval) under single or working-memory load conditions, using cued recall (Experiment 1) and recognition (Experiment 2) procedures. In both experiments the proportional costs of dual tasking were age invariant for semantic retrieval but were particularly marked for episodic retrieval, although the size of the age effect was reduced in recognition compared to cued recall. The data suggest that age effects in dual tasking may be domain specific.  相似文献   
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OBJECTIVE: To test a theoretical model of how ethnic pride and self-control are related to risk and protective factors. DESIGN: A community sample of 670 African American youth (mean age = 11.2 years) were interviewed in households. MAIN OUTCOME MEASURES: Measures of cigarette smoking, alcohol use, and sexual behavior (lifetime to past month). RESULTS: Structural modeling analyses indicated parenting was related to self-control and self-esteem, and racial socialization was related to ethnic pride. Self-control and self-esteem variables were related to levels of deviance-prone attitudes and to perceptions of engagers in, or abstainers from, substance use and sexual behavior. The proximal factors (behavioral willingness, resistance efficacy, and peer behavior) had substantial relations to the criterion variables. Participant gender and parental education also had several paths in the model. Results were generally similar for the 2 outcome behaviors. CONCLUSIONS: In this population, self-esteem and self-control are related to parenting approaches and have pathways to attitudes and social perceptions that are significant factors for predisposing to, or protecting against, early involvement in substance use and sexual behavior.  相似文献   
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Two studies tested the hypothesis that certain positive emotions speed recovery from the cardiovascular sequelae of negative emotions. In Study 1, 60 subjects (Ss) viewed an initial fear-eliciting film, and were randomly assigned to view a secondary film that elicited: (a) contentment; (b) amusement; (c) neutrality; or (d) sadness. Compared to Ss who viewed the neutral and sad secondary films, those who viewed the positive films exhibited more rapid returns to pre-film levels of cardiovascular activation. In Study 2, 72 Ss viewed a film known to elicit sadness. Fifty Ss spontaneously smiled at least once while viewing this film. Compared to Ss who did not smile, those who smiled exhibited more rapid returns to pre-film levels of cardiovascular activation. We discuss these findings in terms of emotion theory and possible health-promoting functions of positive emotions.  相似文献   
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We report an eye movement experiment investigating the influence of the focus operator only on syntactic processing of "long" relative clause sentences. Paterson, Liversedge, and Underwood (1999) found that readers were garden pathed by "short" reduced relative clause sentences containing the focus operator only . They argued that due to thematic differences between "short" and "long" relative clause sentences, garden path effect might not occur when "long" reduced relative clause sentences are read. Eye-tracking data show that garden path effects found during initial processing of the disambiguating verb of "long" reduced sentences without only were absent or delayed in the case of counterparts with only . We discuss our results in terms of current theories of sentence processing.  相似文献   
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Book reviews     
Arnold, M. Memory and the brain. Hillsdale, N. J.: Lawrence Erlbaum Associates. 1984. Pp. 532. ISBN 0-89859-290-9. £47.90.

Green, T. R. G., Payne, S. P. and van der Veer, G. C. (Eds.). The psychology of computer use.. London: Academic Press. 1983. Pp. 225. ISBN 0-12-2974204. $9.50.

Stunkard, A. J. and Stellar, E. (Eds.). Eating and its disorders. New York: Raven Press. 1984. Pp. 302. ISBN 0-89004-891-6. $58.50.

Spillmann, L. and Wooten, B. R. (Eds.) Sensory experience, adaptation, and perception: Festschrift for Zero Kohler. Hillsdale, N. J.: Lawrence Erlbaum Associates. 1984. Pp. xxvii + 748. ISBN 0 8985-3-218-6. £70.85.

Geschwind, N. and Galaburda, A. M. (Eds.)Cerebral dominance: The biological foundations. Cambridge, Mass.: Harvard University Press. 1984. Pp. 232. ISBN 0-674-10658-X. £24.35.

Annett, M. Left, right, hand and brain: The right shift theory. 1985. London and Hillsdale, N. J.: Lawrence Erlbaum Associates. Pp. xiii + 474. ISBN 0-86377418-5 £29.95.

Ericsson, K. A. and Simon, H. A. Protocol analysis: Verbal reports as data. Cambridge, Mass.: The M.I.T. Press. 1984. Pp. 426. ISBN 0-262-05029-3. £28.95.  相似文献   
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OBJECTIVE: Compare the efficacy of a multicomponent social support intervention to standard-of-care counseling on medication adherence among HIV-infected patients initiating antiretroviral therapy. DESIGN: Randomized controlled trial. Generalized estimating equations tested for differences in the percentage of participants achieving 90% adherence. MAIN OUTCOME MEASURES: Pill-taking, electronically monitored over 6 consecutive months; plasma viral load (VL), assessed at 3 and 6 months following initiation of therapy. RESULTS: Of 226 participants who were randomized and began the trial, 87 (38%) were lost to the study by 6 months. The proportion of adherent participants declined steadily over time, with no time by group interaction. Sustained adherence was associated with increased odds of achieving an undetectable VL (OR=1.78; 95% CI=1.01, 3.13). In intention-to-treat analyses, a larger proportion of the intervention group than the control group was adherent (40.15% vs. 27.59%, p=.02) and achieved an undetectable VL p=.04). However, the majority of participants who remained on study experienced some reduction in VL (>or=1-log drop or undetectable), regardless of experimental condition. CONCLUSION: The multicomponent social support intervention significantly improved medication adherence over standard-of-care counseling; evidence for improved virologic outcomes was inconsistent. Early discontinuation of care and treatment may be a greater threat to the health of HIV patients than imperfect medication-taking.  相似文献   
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A series of four spatial localization experiments is reported that examined the effects of display duration and presentation mode on positive and negative priming using an attended-repetition and an ignored-repetition paradigm, respectively. Experiment 1 showed larger positive priming with response-dependent than with 150 ms display durations while negative priming remained unaffected. Experiments 2-4 were performed to further elucidate the effects of prime-probe durations. Data suggest largely independent effects of prime and probe duration on priming effects. Manipulation of prime duration affected facilitation due to repetition of the prime distractor location as well as inhibitory effects associated with ignored repetition. Furthermore, anticipated probe duration modulated the effectiveness of inhibition of return. Findings are discussed within a framework proposing two major components of priming effects—a stimulus-driven or automatic component, and a strategic component related to the participant's expectations towards the probe.  相似文献   
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