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961.
Holcombe AO  Chen WY 《Cognition》2012,123(2):218-228
Driving on a busy road, eluding a group of predators, or playing a team sport involves keeping track of multiple moving objects. In typical laboratory tasks, the number of visual targets that humans can track is about four. Three types of theories have been advanced to explain this limit. The fixed-limit theory posits a set number of attentional pointers available to follow objects. Spatial interference theory proposes that when targets are near each other, their attentional spotlights mutually interfere. Resource theory asserts that a limited resource is divided among targets, and performance reflects the amount available per target. Utilising widely separated objects to avoid spatial interference, the present experiments validated the predictions of resource theory. The fastest target speed at which two targets could be tracked was much slower than the fastest speed at which one target could be tracked. This speed limit for tracking two targets was approximately that predicted if at high speeds, only a single target could be tracked. This result cannot be accommodated by the fixed-limit or interference theories. Evidently a fast target, if it moves fast enough, can exhaust attentional resources.  相似文献   
962.
Curran W  Benton CP 《Cognition》2012,122(2):252-257
Event duration perception is fundamental to cognitive functioning. Recent research has shown that localized sensory adaptation compresses perceived duration of brief visual events in the adapted location; however, there is disagreement on whether the source of these temporal distortions is cortical or pre-cortical. The current study reveals that spatially localized duration compression can also be direction contingent, in that duration compression is induced when adapting and test stimuli move in the same direction but not when they move in opposite directions. Because of its direction-contingent nature, the induced duration compression reported here is likely to be cortical in origin. A second experiment shows that the adaptation processes driving duration compression can occur at or beyond human cortical area MT+, a specialized motion center located upstream from primary visual cortex. The direction-specificity of these temporal mechanisms, in conjunction with earlier reports of pre-cortical temporal mechanisms driving duration perception, suggests that our encoding of subsecond event duration is driven by activity at multiple levels of processing.  相似文献   
963.
Hoarding is a serious form of psychopathology that has been associated with significant health and safety concerns, as well as the source of social and economic burden (Tolin, Frost, Steketee, & Fitch, 2008; Tolin, Frost, Steketee, Gray, & Fitch, 2008). Recent developments in the treatment of hoarding have met with some success for both individual and group treatments. Nevertheless, the cost and limited accessibility of these treatments leave many hoarding sufferers without options for help. One alternative is support groups that require relatively few resources. Frost, Pekareva-Kochergina, and Maxner (2011) reported significant declines in hoarding symptoms following a non-professionally run 13-week support group (The Buried in Treasures [BIT] Workshop). The BIT Workshop is a highly structured and short term support group. The present study extended these findings by reporting on the results of a waitlist control trial of the BIT Workshop. Significant declines in all hoarding symptom measures were observed compared to a waitlist control. The treatment response rate for the BIT Workshop was similar to that obtained by previous individual and group treatment studies, despite its shorter length and lack of a trained therapist. The BIT Workshop may be an effective adjunct to cognitive behavior therapy for hoarding disorder, or an alternative when cognitive behavior therapy is inaccessible.  相似文献   
964.
In a long-lag morphological priming experiment, Dutch (L1)-English (L2) bilinguals were asked to name pictures and read aloud words. A design using non-switch blocks, consisting solely of Dutch stimuli, and switch-blocks, consisting of Dutch primes and targets with intervening English trials, was administered. Target picture naming was facilitated by morphologically related primes in both non-switch and switch blocks with equal magnitude. These results contrast some assumptions of sustained reactive inhibition models. However, models that do not assume bilinguals having to reactively suppress all activation of the non-target language can account for these data.  相似文献   
965.
This study investigated how early experience with racial discrimination affected the subsequent risky sexual behaviors of a diverse sample of African American youths (N = 745). The analyses focused on 3 risk-promoting factors thought to mediate the hypothesized discrimination → risky sex relation: negative affect, affiliation with deviant peers, and favorable attitudes toward risky sex. In addition, attentive parenting was examined as a protective factor. Analyses using structural equation modeling revealed that youths who perceived more racial discrimination at age 10 or 11 were engaging in more sexual risk taking at age 18 or 19. This relation was mediated by the hypothesized risk-promoting factors via pathways that were consistent with our conceptual model. Results also indicated a prospective reciprocal relation between parenting and children's deviant affiliations: deviant peer affiliations at age 10 or 11 predicted more attentive parenting behaviors by the parents; this response from the parents, in turn, predicted relatively fewer deviant affiliations when the youths were 15 or 16. Study findings are discussed in terms of their relevance to the disproportionately high rates of sexually transmitted infections among African Americans.  相似文献   
966.
A widely held assumption in metamemory is that better, more accurate metamemory monitoring leads to better, more efficacious restudy decisions, reflected in better memory performance--we refer to this causal chain as the restudy selectivity hypothesis. In 3 sets of experiments, we tested this hypothesis by factorially manipulating metamemory monitoring accuracy and self-regulation of study. To manipulate monitoring accuracy, we compared judgments of learning (JOLs) made contemporaneously with a delayed retrieval attempt to JOLs either made at a delay without attempting retrieval or made immediately after study; in previous studies, delayed retrieval-based JOLs have robustly predicted recall with greater relative accuracy than have the other JOL types. To manipulate self-regulation of study, in Experiments 1A-1C and 2A-2C, we compared conditions in which participants' restudy selections were honored with conditions in which they were completely or randomly dishonored; in Experiments 3A-3C, we randomly honored or dishonored half of the restudy selections and half of the nonselections. Results revealed that the benefit of delayed, retrieval-based JOLs for final memory performance was due largely to the selection of more items for restudy rather than to better discriminations between items that would benefit more versus less from restudy. In most cases, gains in recall due to greater self-regulation of study did not increase with better monitoring accuracy; when they did, the effect was extremely small. The surprising conclusion was that restudy decisions were not very much more efficacious under conditions that yield greater monitoring accuracy than under those that do not.  相似文献   
967.
Research reports the perpetuation of communal traits by transgender women, possibly to affirm their core gender identity. Transgender women in the United States are nearly 6 times more likely than the general population to experience significant depressive symptoms. Studies among non-transgender individuals in the United States demonstrate that agentic traits are associated with less depressive symptoms, while studies on communal traits are more inconsistent in their association with indicators of depression. Our study’s central objective was to examine the associations of agency and communion with depression and resilience (i.e., personal competence and acceptance of self and life) among transgender women living part-time and full-time in the female gender role. Participants in the United States were recruited through online and offline purposive sampling. One hundred and twenty-two transgender women (primarily Caucasian; ages ranging from 22 to 75) completed a web-based questionnaire. Results indicated that agentic and communal traits were significantly associated with decreased symptoms of depression and increased levels of resilience. One component of resilience – acceptance of self and life – mediated the relationship between agentic/communal traits and depression, however, for communal traits this pattern was only found for transgender women living in the female role full-time. There were no significant differences on depressive symptoms and one component of resilience - personal competence – among transgender women living full-time compared to transgender women living in the female role part-time. Transgender women living full-time in the female gender role reported higher levels of agentic/communal traits and acceptance of self and life compared to those living part-time in the female gender role. Our findings are discussed in the context of mental health among transgender women.  相似文献   
968.
There are twice as many suicides as homicides in the United States, and the suicide rate is rising. Suicides increased 12% between 1999 and 2009. Mental health professionals often treat suicidal patients, and suicide occurs even among patients who are seeking treatment or are currently in treatment. Despite these facts, training of most mental health professionals in the assessment and management of suicidal patients is surprisingly limited. The extant literature regarding the frequency with which mental health professionals encounter suicidal patients is reviewed, as is the prevalence of training in suicide risk assessment and management. Most importantly, six recommendations are made to address the longstanding insufficient training within the mental health professions regarding the assessment and management of suicidal patients.  相似文献   
969.
Occurrence of the home disadvantage in professional ice hockey was examined by analyzing shootout data from 2005 through 2008. Results indicated that teams involved in shootouts playing at their home arenas did not lose significantly more games at home than on the road. Results did not support the hypotheses that emphasize the roles of physical contact and diffusion of responsibility in accounting for past failures to find the home disadvantage in professional ice hockey.  相似文献   
970.
Alcohol use and its associated problems among university students have attracted empirical investigation by researchers and scholars. While many of these studies have reported a very high level of alcohol consumption and highlighted the various problems this portends, alcohol-related perceptions of this vulnerable population, which could be germane to intervention aimed at curtailing the problem, have remained largely under-researched. This cross-sectional survey examined the use and perceptions of alcohol by student-patrons (n = 1,705) of beer parlours or ‘joints’ in three university communities in Southwest Nigeria. Respondents were interviewed using AUDIT, a socio-demographic prototype and an open-ended section on alcohol-related perceptions of the students. Findings indicated that overall, 72% of the respondents perceived that alcohol is good for socializing, 68% perceived that alcohol is good in the aspect of stress reduction, 58% believed that alcohol consumption is indicative of maturity, 36% perceived that alcohol enhances their sexual performance while 39% perceived that alcohol serves to enhance alertness/concentration. Results also showed that gender (β = −. 23; p < .05), paternal alcohol use (β = .36; p < .01), parental socio-economic status (β = .33; p < .01), and residential status of university of respondents (β = .21; p < .05) significantly predicted alcohol use. The study concluded that perceptions about alcohol are very germane to understanding students’ alcohol use and should be reckoned with in designing intervention programmes. The need to adopt a ‘client-centered’ approach to the problem of student drinking behaviour was emphasized.  相似文献   
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