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171.
The authors examined the effect of adaptation to expansion on overtaking maneuvers in a driving simulator. Following driving on a straight empty road for 5 min, drivers initiated overtaking substantially later (220-510 ms) than comparable maneuvers made following viewing a static scene or following 5 min of curve driving. Following adaptation to contraction (produced by driving backward), observers initiated overtaking significantly sooner. The removal of the road texture significantly reduced the size of the adaptation effect. The authors propose that these changes in overtaking behavior are due to misestimation of the time headway produced by local adaptation of looming detectors that signal motion-in-depth for objects near the focus of expansion. This adaptation effect may increase the risk of rear-end collisions during highway driving.  相似文献   
172.
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   
173.
The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words. Here we show that this carry-over effect is present in heroin addicts-but not control subjects-in a heroin Stroop task, and in normal subjects in a stress Stroop task. Thus, the effect generalizes to other populations. In addition, an examination of the studies that have collected data from both mixed and blocked formats provides converging evidence for the presence of carry-over effects. We discuss the implications of the carry-over effect for research using the emotional Stroop task.  相似文献   
174.
Previous research has demonstrated that it is possible to induce biases in the interpretation of ambiguous text passages by training. Participants consistently trained to interpret emotionally ambiguous passages in either a negative or positive direction show training-congruent effects when presented with new ambiguous material. These training effects are demonstrated by participants' subsequent recognition ratings for disambiguating sentences, which represent both possible meanings of the novel ambiguous test passages. In this series of experiments, we investigated the durability of these training effects over time spans of up to 1 day and found them to be robust. The findings encourage us to believe that induced biases may serve as a useful analogue to those observed clinically.  相似文献   
175.
This study examined the psychometric properties of the Revised Child Anxiety and Depression Scale (RCADS) in a clinical sample of 513 youth referred for mental health assessment at a university clinic. Internal consistency and factor analysis provided support for the factorial validity of the RCADS. Convergent and discriminant validity tests against both clinical interview and self-report criteria also suggested favorable properties of the RCADS. In comparative tests with traditional measures of anxiety and depression, the RCADS generally showed greater correspondence to specific diagnostic syndromes. Clinical cutoffs are reported for the purposes of future clinical and research applications.  相似文献   
176.
This investigation compared the likelihood of insomnia and insomnia-related health consequences among individuals of different socioeconomic status. A random-digit dialing procedure was used to recruit at least 50 men and 50 women in each age decade from 20 to 80+ years old. Participants completed 2 weeks of sleep diaries as well as questionnaires related to fatigue, sleepiness, and psychological distress. Socioeconomic status was measured by education status assessed at 3 different levels: individual, household, and community. Results indicated that individuals of lower individual and household education were significantly more likely to experience insomnia even after researchers accounted for ethnicity, gender, and age. Additionally, individuals with fewer years of education, particularly those who had dropped out of high school, experienced greater subjective impairment because of their insomnia.  相似文献   
177.
Negatively valenced stimuli foster cognitive impairment in schizotypy and schizophrenia. To identify relevant brain mechanisms, the authors had 16 positive-schizotypy and 16 control participants perform an emotional Stroop task, judging the ink color of negative and neutral words during functional magnetic resonance imaging (fMRI) of regional brain activity. Schizotypy individuals showed increased right and decreased left activity in dorsolateral prefrontal cortex, indicating a deficit in maintenance of attentional set in the presence of negative emotional distractors. They also showed abnormal activity in ventral limbic areas, including decreased activity in nucleus accumbens and increased activity in hippocampus and amygdala, a circuit involved in the integration of cognitive and affective processes. These results indicate that aspects of emotion-cognition processes and the brain mechanisms that implement them are similar in schizotypy and schizophrenia.  相似文献   
178.
Although functional neuroimaging studies of human decision-making processes are increasingly common, most of the research in this area has relied on passive tasks that generate little individual variability. Relatively little attention has been paid to the ability of brain activity to predict overt behavior. Using functional magnetic resonance imaging (fMRI), we investigated the neural mechanisms underlying behavior during a dynamic decision task that required subjects to select smaller, short-term monetary payoffs in order to receive larger, long-term gains. The number of trials over which the longterm gains accrued was manipulated experimentally (2 versus 12). Event-related neural activity in right lateral prefrontal cortex, a region associated with high-level cognitive processing, selectively predicted choice behavior in both conditions, whereas insular cortex responded to fluctuations in amount of reward but did not predict choice behavior. These results demonstrate the utility of a functional neuroimaging approach in behavioral psychology, showing that (a) highly circumscribed brain regions are capable of predicting complex choice behavior, and (b) fMRI has the ability to dissociate the contributions of different neural mechanisms to particular behavioral tasks.  相似文献   
179.
Previous research with speeded-response interference tasks modeled on the Garner paradigm has demonstrated that task-irrelevant variations in either emotional expression or facial speech do not interfere with identity judgments, but irrelevant variations in identity do interfere with expression and facial speech judgments. Sex, like identity, is a relatively invariant aspect of faces. Drawing on a recent model of face processing according to which invariant and changeable aspects of faces are represented in separate neurological systems, we predicted asymmetric interference between sex and emotion classification. The results of Experiment 1, in which the Garner paradigm was employed, confirmed this prediction: Emotion classifications were influenced by the sex of the faces, but sex classifications remained relatively unaffected by facial expression. A second experiment, in which the difficulty of the tasks was equated, corroborated these findings, indicating that differences in processing speed cannot account for the asymmetric relationship between facial emotion and sex processing. A third experiment revealed the same pattern of asymmetric interference through the use of a variant of the Simon paradigm. To the extent that Garner interference and Simon interference indicate interactions at perceptual and response-selection stages of processing, respectively, a challenge for face processing models is to show how the same asymmetric pattern of interference could occur at these different stages. The implications of these findings for the functional independence of the different components of face processing are discussed.  相似文献   
180.
Optimism and pessimism are personality variables that have repeatedly been shown to affect health, job performance, and social relationships. Various instruments purport to measure these dispositions that differ substantially in their theoretical and measurement models. While research has examined relations between subsets of these measures, their unique predictive ability has been neglected. Three sequential studies evaluated the interrelation and predictive ability of the three most utilized instruments, the Life Orientation Test (LOT), the O/P Instrument (OPI) and variants of the Attributional Style Questionnaire (ASQ). Consistent with expectations, measures sharing a future-expectancy component (LOT and OPI) were moderately related and most predictive of health, depression, and coping. ASQ measures were modestly related to the LOT and OPI and offered less consistent predictions.  相似文献   
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