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191.
We review recent advances in the understanding of the mechanisms of change that underlie cognitive development. We begin by describing error-driven, self-organizing and constructivist learning systems. These powerful mechanisms can be constrained by intrinsic factors, other brain systems and/or the physical and social environment of the developing child. The results of constrained learning are representations that themselves are transformed during development. One type of transformation involves the increasing specialization and localization of representations, resulting in a neurocognitive system with more dissociated streams of processing with complementary computational functions. In human development, integration between such streams of processing might occur through the mediation of language.  相似文献   
192.
A prospective examination of body image and smoking cessation in women   总被引:2,自引:2,他引:0  
This study prospectively examined body image in a community sample of women smokers (N = 141, 89% European–American, M age = 39.5, M BMI = 25.5) participating in a 12-week randomized smoking cessation trial. Participants completed measures assessing subjective and perceptual aspects of body image. Regression analyses showed that subjective body image was predictive of smoking rate at the end of treatment. A MANCOVA revealed that perceptual body image (body size estimation) significantly predicted smoking cessation. Quitting smoking actually worsened body image, although these results were no longer significant after controlling for weight gain. Results support the theory that a negative body image may hamper cessation attempts. In addition, weight gain during smoking cessation may adversely impact body image and lead to an increased risk for relapse.  相似文献   
193.
The present work investigated mechanisms by which Whites' prejudice toward Blacks can be reduced (Study 1) and explored how creating a common ingroup identity can reduce prejudice by promoting these processes (Study 2). In Study 1, White participants who viewed a videotape depicting examples of racial discrimination and who imagined the victim's feelings showed greater decreases in prejudice toward Blacks than did those in the objective and no instruction conditions. Among the potential mediating affective and cognitive variables examined, reductions in prejudice were mediated primarily by feelings associated with perceived injustice. In Study 2, an intervention designed to increase perceptions of a common group identity before viewing the videotape, reading that a terrorist threat was directed at all Americans versus directed just at White Americans, also reduced prejudice toward Blacks through increases in feelings of injustice.  相似文献   
194.
Resilient teachers: resisting stress and burnout   总被引:5,自引:0,他引:5  
In Australia, the incidence of teacher stress and burnout has caused serious concern. Many studies of teacher stress have focused on the dysfunctional strategies of individual teachers – in other words they have adopted a deficit approach to the problem with the focus firmly fixed on whats going wrong. From this perspective, the failure of some teachers to cope has generally been defined as a personal rather than an institutional weakness and the solutions that have been promoted have been largely palliative or therapeutic. The study reported in this paper adopted a different approach to the question of teacher stress and burnout. Instead of asking whats going wrong we asked why are some teachers able to cope successfully with the same kinds of stressors that appear to defeat others – in other words, we looked at whats going right.  相似文献   
195.
Perceptual completion consists of bridging the gaps imposed by occlusion, such as perceiving the unity of center-occluded objects. It is unknown at present what developmental mechanisms underlie the emergence of functional perceptual completion in infancy. One current debate centers on the role of visible surface motion. According to a core-principles account, perceptual completion emerges simultaneously with the onset of motion discrimination, the sole determinant of unity percepts in infants. According to a contrasting constructivist account, motion discrimination is but one of several independent inputs to perceptual completion. In the present study, 2-month-old infants were tested for both unity perception and motion discrimination in partial-occlusion displays. Motion discrimination obtained under all conditions, even under circumstances in which infants were unable to perceive completion. Four-month-olds showed marked improvements in perceptual completion, most likely because of improvements in information integration. Taken together, these findings support a constructivist view of early perceptual and cognitive development.  相似文献   
196.
Efforts to better understand bipolar spectrum disorders across ethnic groups are often hampered by the lack of commonly used self-report instruments to assess mania and depression in individuals who speak languages other than English. This article describes the translation into Spanish of 2 self-report measures of manic symptoms (i.e., the Internal State Scale and the Hypomanic Personality Scale) and 2 self-report measures of depression (i.e., the Inventory to Diagnose Depression and the Inventory to Diagnose Depression, Lifetime version). The authors translated these measures into Spanish and assessed their psychometric properties among bilingual college students (N = 88). Results suggest that the Spanish versions have psychometric properties comparable to the English versions of the instruments.  相似文献   
197.
There are specific challenges to studying the design of pharmacologic trials in child/adolescent and adult autism, such as subject stratification and parallel versus crossover designs. This article describes how optimal study design is influenced by subject selection and outcome measures chosen. Lessons learned in study design from the Research Units on Pediatric Psychopharmacology Autism Network trial with risperidone, Seaver Center trials with fluoxetine and valproate, Dartmouth trials with amantadine, and National Institutes of Health secretin trials are highlighted. The Internet System for Assessing Autistic Children system for managing multicenter clinical trials in autism and statistical issues in autism research are also described.  相似文献   
198.
The present study examined performance during 3 hr. of simulated sentry duty with and without the intermittent administration of low-level sensory stimuli (odor or vibration). For odor and control conditions, target-detection latency increased steadily over the course of the 3-hr. session. Administration of a tactile stimulus reduced the increase in detection latency compared to that found in odor and control conditions. For all conditions, there were no significant differences in target-detection frequency, shot accuracy, or friend-foe discrimination. Across all conditions, restlessness (motor activity) increased significantly the first hour and remained elevated for the rest of the session. Subjective measures of workload (NASA-TLX) indicated that the 3-hr. task rated high on physical demand, mental demand, frustration, and overall workload. These findings suggest that the intermittent delivery of a clearly detectable tactile stimulus can reduce reaction-time decrements that occur as time on task increases.  相似文献   
199.
Infants' understanding of toy model-real exemplar relations was assessed through preferential looking and habituation tasks. Results from the preferential looking task suggest that 18-month toddlers are just beginning to demonstrate comprehension of symbolic relations between iconic models and their real object counterparts. Performance of 10- and 14-month-old infants in the preferential looking task did not improve when across-domain pairs of videos were used in place of within-domain pairs. Habituation task results indicated that 10-month-olds do not comprehend symbolic relations between miniature toy replicas and their "real" counterparts, but that such understanding begins to emerge by age 14 months. Interactions between symbolic processing and early lexical development are considered, as are methodological implications for the study of infant categorization.  相似文献   
200.
Johnson HD 《Adolescence》2004,39(154):243-255
Previous research has examined gender and grade differences in the emotional closeness of adolescents' same- and cross-sex friendships. However, findings from these studies have been inconsistent because they have failed to (1) differentiate between cross-sex friendships and romantic relationships and (2) compare same- and cross-sex friendships. In an attempt to clarify previous findings, gender and grade differences in adolescent reports of emotional closeness within same- and cross-sex friendships were examined in the current study. Responses from two hundred seventy adolescents indicated gender differences in reports of time spent with their friends daily and levels of relationship closeness, cohesion, and commitment. Further, grade moderated relationship differences in reports of relationship cohesion and closeness. Differences in predictors of intimacy support previous studies that have found grade and gender differences in levels of intimacy in adolescents' same- and cross-sex friendships. Results also elaborate on previous research by indicating grade differences in adolescents' perceptions of cohesion and closeness in their same- and cross-sex friendships. Findings are discussed in terms of understanding differences in adolescent reports of intimacy within same- and cross-sex friendships.  相似文献   
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