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991.
Treatment and rehabilitation of the cognitive, psychological, and motor sequelae of central nervous system dysfunction often relies on assessment instruments to inform diagnosis and to track changes in clinical status. Typically, these assessments employ paper-and-pencil psychometrics, hands-on analog/computer tests, and rating of behavior within the context of real-world functional environments. Virtual reality offers the option to produce and distribute identical "standard" simulation environments in which performance can be measured and rehabilitated. Within such digital scenarios, normative data can be accumulated for performance comparisons needed for assessment/diagnosis and for treatment/rehabilitation purposes. In this manner, reusable archetypic virtual environments constructed for one purpose can also be applied for applications addressing other clinical targets. This article will provide a review of such a retooling approach using a virtual classroom simulation that was originally developed as a controlled stimulus environment in which attention processes could be systematically assessed in children with attention-deficit/hyperactivity disorder. This system is now being applied to other clinical targets including the development of tests that address other cognitive functions, eye movement under distraction conditions, social anxiety disorder, and the creation of an earthquake safety training application for children with developmental and learning disabilities. 相似文献
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993.
Downie M Mageau GA Koestner R Liodden T 《Cultural diversity & ethnic minority psychology》2006,12(3):527-540
In the present study the authors used an event-contingent daily recording strategy, the Rochester Interaction Record, to examine the relation of perceived evaluations of a multicultural person's heritage group to the nature and quality of his or her social interactions. Hierarchical linear modeling showed that having an interaction partner who positively evaluated one's heritage culture was associated with significantly enhanced interaction intimacy, disclosure, and quality, as well as with feelings of personal acceptance. Moderator analyses revealed that individuals who possessed a chameleon-like cultural identity and those who had low public collective self-esteem were particularly reactive to how their heritage group was being evaluated. 相似文献
994.
Yonker JE Adolfsson R Eriksson E Hellstrand M Nilsson LG Herlitz A 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2006,13(3-4):291-307
Studies of hormone therapy (HT) and cognition have yielded conflicting results. The aim of this observational study was to examine the effect of estradiol, via serum verified HT (estradiol, estriol, progesterone) and endogenous estradiol, on 108 healthy postmenopausal women's cognitive performance. The results demonstrated that the 43 HT-users performed at a significantly higher level than non-users on episodic memory tasks and on a verbal fluency task, whereas HT-users and non-users did not differ on tasks assessing semantic memory and spatial visualization. In addition, there was a positive relationship between serum estradiol level and episodic memory performance, indicating that postmenopausal HT is associated with enhanced episodic memory and verbal fluency, independent of age and education. These observational results suggest that HT use may be sufficient to exert small, yet positive effects on female sensitive cognitive tasks. Hormone therapy compliance and formulation is discussed as confounding factors in previous research. 相似文献
995.
Dresser R 《Theoretical medicine and bioethics》2006,27(2):115-139
Pharmaceutical companies are major sponsors of biomedical research. Most scholars and policymakers focus their attention on
government and academic oversight activities, however. In this article, I consider the role of pharmaceutical companies’ internal
ethics statements in guiding decisions about corporate research and development (R&D). I review materials from drug company
websites and contributions from the business and medical ethics literature that address ethical responsibilities of businesses
in general and pharmaceutical companies in particular. I discuss positive and negative uses of pharmaceutical companies’ ethics
materials and describe shortcomings in the companies’ existing ethics programs. To guide employees and reassure outsiders,
companies must add rigor, independence, and transparency to their R&D ethics programs. 相似文献
996.
997.
998.
Neural bases of binocular rivalry 总被引:9,自引:0,他引:9
During binocular rivalry, conflicting monocular images compete for access to consciousness in a stochastic, dynamical fashion. Recent human neuroimaging and psychophysical studies suggest that rivalry entails competitive interactions at multiple neural sites, including sites that retain eye-selective information. Rivalry greatly suppresses activity in the ventral pathway and attenuates visual adaptation to form and motion; nonetheless, some information about the suppressed stimulus reaches higher brain areas. Although rivalry depends on low-level inhibitory interactions, high-level excitatory influences promoting perceptual grouping and selective attention can extend the local dominance of a stimulus over space and time. Inhibitory and excitatory circuits considered within a hybrid model might account for the paradoxical properties of binocular rivalry and provide insights into the neural bases of visual awareness itself. 相似文献
999.
This investigation extends previous research documenting differences in Chinese and European American infants' facial expressivity. Chinese girls adopted by European American families, nonadopted Mainland Chinese girls, nonadopted Chinese American girls, and nonadopted European American girls responded to emotionally evocative slides and an odor stimulus. European American girls smiled more than Mainland Chinese and Chinese American girls and scored higher than Mainland Chinese girls for disgust-related expressions and overall expressivity. Adopted Chinese girls produced more disgust-related expressions than Mainland Chinese girls. Self-reported maternal strictness, aggravation, positive expressiveness, and cultural identification correlated with children's facial responses, as did number of siblings and adults in the home. Results suggest that culture and family environment influences facial expressivity, creating differences among children of the same ethnicity. 相似文献
1000.
Espeseth T Greenwood PM Reinvang I Fjell AM Walhovd KB Westlye LT Wehling E Lundervold A Rootwelt H Parasuraman R 《Cognitive, affective & behavioral neuroscience》2006,6(1):31-43
In the present study, we investigated age-related changes in interactions between efficiency of neuronal repair mechanisms
and efficiency of cholinergic neurotransmission in the context of attentional orienting. In addition, we explored white matter
volume changes as possible neuronal underpinnings. A sample of 230 healthy middle-aged (53–64 years) and older (65–75 years)
adults was genotyped for polymorphisms of APOE and CHRNA4, a nicotinic receptor subunit gene. Participants were administered
a visuospatial attention task involving letter discrimination with location cues of varying validity. Genotype effects on
white matter volume were also investigated in a subset of participants who received MRI scans. APOE interacted with CHRNA4,
such that APOE-ε4 carriers who were also CHRNA4 TT homozygotes showed disproportionately slowed reaction time (RT) following
invalid location cues. The interaction was stronger in the middle-aged participants than in the older participants. There
was also a trend for individuals with combined APOE-ε4/CHRNA4 TT genotypes to show both lower white matter volume and slower
overall RT on the attention task. The interaction of a neurotransmission gene (CHRNA4) and a susceptibility gene (APOE) suggests
that the efficiency of neuronal repair mechanisms may modulate the cholinergic system to influence attentional function. 相似文献