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211.
Prior exposure to drugs of abuse has been shown to occlude the structural plasticity associated with living in a complex environment. Amphetamine treatment may also occlude some cognitive advantages normally associated with living in a complex environment. To test this hypothesis we examined the influence of prior exposure to amphetamine on fear conditioning in rats housed in either a standard or complex environment. Housing in a complex environment facilitated fear learning to an auditory conditioned stimulus (CS), but not to the training context, relative to animals housed singly or in a social group. Prior treatment with amphetamine eliminated this effect. These results indicate that living in a complex environment facilitates conditional freezing to an auditory CS, and that this effect is abolished by pretreatment with amphetamine.  相似文献   
212.
To provide a better estimate of the prevalence of ADHD in adulthood, the authors complete a telephone survey of 966 randomly selected adults. They compute two diagnoses from the survey data. Participants meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for both childhood and adulthood are defined as narrow ADHD. Broad ADHD adds to that definition those meeting subthreshold criteria. Cronbach's alpha is .90 for the 18 DSM-IV symptoms in childhood and .88 when rated for current symptoms in adulthood. No one item unduly influences the reliability of the total score. The authors find similar results in separate analyses of hyperactive-impulsive and inattentive symptoms. They estimate prevalences of 2.9% for Narrow ADHD and 16.4% for Broad ADHD. Having ADHD is associated with lower levels of education and employment status. These findings suggest that adult ADHD is a common disorder associated with impaired functioning.  相似文献   
213.
The paper begins by situating Singer within the British meta-ethical tradition. It sets out the main steps in his argument for utilitarianism as the ‘default setting’ of ethical thought. It argues that Singer’s argument depends on a hierarchy of reasons, such that the ethical viewpoint is understood to be an adaptation – an extension – of a fundamental self-interest. It concludes that the argument fails because it is impossible to get from this starting-point in self-interest to his conception of the ethical point of view. The fundamental problem is its mixing the immiscible: the Humean subordination of reason to interest with the Kantian conception of reason as universal and authoritative.  相似文献   
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This article reports on the feasibility of using interactive voice response (IVR) technology to obtain daily reports of attitudes toward alcohol and tobacco use among children 9–13 years of age. Two studies were conducted. The first was an investigation of the use of IVR technology to obtain daily data from a sample of primary school children over a period of 8 weeks. The second was an extension of the research to a large sample of primary and secondary school children in urban and rural areas who provided daily data over a 4-week period. Retention and compliance rates comparable to those obtained with adults were evident in both studies, supporting the feasibility of this technology with children. The results are discussed in relation to the benefits of this methodology for health research, particularly for studies of sensitive topics conducted with children and adolescents.  相似文献   
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Research has indicated that random physical practice of a motor skill enhances effects of long-term learning more than blocked practice. Moreover, the use of mental rehearsal coupled with physical practice has been shown to accelerate motor skill acquisition in many different contexts and is better than no practice at all. Others have found that some mental rehearsal strategies are better than others for maximizing performance. This study examined how combinations of mental and physical practice schedules affected the learning of a coincidence timing task. 30 college students were randomly assigned to one of four treatment groups involving combinations of imagery and physical practice. Three tasks were utilized, each involving a particular speed (slow, medium, fast) on the Bassin Anticipation Timer. Conclusions were based on a three-way analysis of variance, using type of mental practice, type of physical practice, and sex as between-group factors, conducted separately for acquisition and retention trials. Type of physical practice was significantly related to performance. On the acquisition trials, random practice was associated with larger mean errors than blocked practice; however, the reverse was true for retention trials. There was no significant effect of type of mental practice in either the acquisition or retention phase. Sex was significantly related to performance for the retention trials only, where the 15 men made smaller errors than the 15 women.  相似文献   
218.
This investigation most importantly sought to illustrate the use of social science to promote cross-cultural dialogue. Fukuyama (1992) explained contemporary cultural trends in terms of a triumphant individualism that would overcome all other forms of social life, including what he described as the “fundamentalist resentment” of Iran. Lasch (1979) more pessimistically diagnosed Western social arrangements in terms of an emerging “culture of narcissism.” In this study, Iranian and American university students responded to measures of narcissism, individualist and collectivist values, religious interest, and psychological adjustment (identity, self-actualization, and self-consciousness). Variables related to a sense of community (collectivist values, religious interest, and identity) correlated negatively with narcissism in both societies, as did self-actualization. These data supported a moderate position between the polarized extremes of Fukuyama and Lasch and more importantly demonstrated how social scientific methods might be useful in creating a “space” for conducting a “dialogue between civilizations.”  相似文献   
219.
Developmental antecedents to adult emotional functioning were investigated in an epidemiologic study using theories of personality and emotion. The authors tested whether different types of adult emotional distress can be linked to childhood personality attributes. Using data from 3,138 children at age 7, measures of 4 childhood personality attributes were developed and validated: Behavioral Inhibition, Distress Proneness, Attention, and Inappropriate Interpersonal Self-Regulation. Sound psychometric properties of these scales are demonstrated by considering the measures across multiple samples and in comparison with established child behavior measures. Emotional distress measures were obtained for 694 of these individuals at age 35. Of the personality attributes, 3 of 4 (except behavioral inhibition) predicted general levels of distress as well as specific aspects of adult emotional functioning.  相似文献   
220.
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