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911.
ABSTRACT Abnormal shoulder and elbow muscle coactivation patterns, or muscle synergies, are commonly present following stroke and may arise through dysfunctional descending neural control from the cortex. The authors evaluated a novel technique for examining corticomotor movement encoding of the upper limb in three dimensions. A 6-degree-of-freedom loadcell recorded arm twitch responses in healthy adults following stimulation over the cortex or over Erb's point in the periphery. Stimuli were delivered while the arm generated a 5 N preload in each of the 6 axial directions. The initial force twitch response to stimulation was used to construct twitch direction vectors for each preload direction. General linear mixed model analyses were used to determine the influence of stimulation location, preload direction, posture, and stimulation intensity on twitch direction. Cortical stimulation gave rise to arm twitch responses that were predictably modified by preload direction. Peripheral stimulation elicited stereotypical twitches that were not influenced by preload. Our stimulation, recording, and analysis techniques were able to capture movement encoding of the upper limb in three dimensions. Such techniques could be utilized in the stroke population to determine and monitor the presence of upper limb synergies during muscle activation.  相似文献   
912.
A key ingredient in the current proposal of the DSM-5 Work Group on Personality and Personality Disorders is the assessment of overall severity of impairment in personality functioning: the Levels of Personality Functioning Scale (LPFS). The aim of this article is to contribute a conceptual and empirical discussion of the LPFS from the perspective of the Operationalized Psychodynamic Diagnosis (OPD) system (OPD Task Force, 2008 ). First, we introduce the OPD Levels of Structural Integration Axis (OPD-LSIA), a measure of individual differences in severity of personality dysfunction that is rooted in psychodynamic theory. We show that the OPD-LSIA is reliable, valid, and highly associated with observer ratings of personality disorders. In the second part, we present results from an OPD expert consensus study exploring potential limitations of the current LPFS item set from the perspective of the OPD-LSIA. We conclude with highlighting implications for future revisions of the DSM-5 proposal.  相似文献   
913.
We explored the relations among stress, emotional support, and differentiation of self from the family of origin as predictors of psychological distress in a sample of 200 college students. First, we investigated the discrepant findings of Murdock and Gore (Contemp Fam Ther 23: 319–335, 2004) and Skowron et al. (J Couns Dev 82: 69–78, 2004) regarding the relationships among stress, differentiation, and symptoms (a question of mediation vs. moderation). Second, we examined the role of emotional support in concert with stress and differentiation. When both stressful events and perceived stress were measured, differentiation of self was found to be a significant partial mediator of their effects on psychological distress. Emotional support was also found to partially mediate the relationship between differentiation of self and psychological distress. Differentiation of self partially mediated the relationship between actual and perceived stress, and perceived stress partially mediated the relationship between differentiation of self and psychological distress.  相似文献   
914.
Benchmarking is a program evaluation approach that can be used to study whether the outcomes of parents/children who participate in an evidence-based program in the community approximate the outcomes found in randomized trials. This paper presents a case illustration using benchmarking methodology to examine a community implementation of Parent–Child Interaction Therapy (CI-PCIT) utilized as a child maltreatment prevention effort. Data were collected from 83 parent–child dyads. Change scores were compared to treatment and control effect sizes aggregated from the PCIT literature. Pre-post results indicated significant positive changes in child behavior for CI-PCIT completers. Benchmarking analyses revealed that parents who completed CI-PCIT reported significantly greater positive child outcomes than the aggregate control group benchmark, and significantly less than observed in the treatment benchmark. A summary of decision points and implications for utilizing this methodology in the child maltreatment field are postulated.  相似文献   
915.
916.
Sources of individual differences in scientific problem solving were investigated. Participants representing a wide range of experience in geology completed tests of visuospatial ability and geological knowledge, and performed a geological bedrock mapping task, in which they attempted to infer the geological structure of an area in the Tobacco Root Mountains of Montana. A Visuospatial Ability × Geological Knowledge interaction was found, such that visuospatial ability positively predicted mapping performance at low, but not high, levels of geological knowledge. This finding suggests that high levels of domain knowledge may sometimes enable circumvention of performance limitations associated with cognitive abilities.  相似文献   
917.
Two experiments using an immersive virtual reality foraging environment determined the spatial strategies spontaneously deployed by people in a foraging task and the effects on immediate serial recall of trajectories though the foraging space, which could conform or violate specific organisational constraints. People benefitted from the use of organised search patterns when attempting to monitor their travel though either a clustered "patchy" space or a matrix of locations. The results are discussed within a comparative framework.  相似文献   
918.
Perceptions of coronary heart disease (CHD) influence individual health behavior, which is central to preventing the disease. Not enough is known about the demographic differences in perceptions of CHD among Chinese communities. This study examined these differences in the perceived seriousness and risk of CHD among Hong Kong Chinese. A self-developed questionnaire was administered to a convenient sample (n = 236). Significant differences were identified in the perceived seriousness and risk of CHD between younger and older age groups (p < 0.001) and groups with lower and higher education levels (p < 0.001), but not between genders (p > 0.05). Over 50% of participants expressed greater concern about infectious disease than about CHD, while two-thirds to over half of female, older, and less educated participants were more concerned about stroke. This study highlighted populations with lower levels of CHD perception that need increased public education. The findings have implications for the societal readiness to establishing ongoing public healthcare strategies to increase awareness of CHD.  相似文献   
919.
This study investigated prospective links between quality of the early caregiving environment and children's subsequent executive functioning (EF). Sixty-two families were met on five occasions, allowing for assessment of maternal interactive behavior, paternal interactive behavior, and child attachment security between 1 and 2 years of age, and child EF at 2 and 3 years. The results suggested that composite scores of parental behavior and child attachment were related to child performance on EF tasks entailing strong working memory and cognitive flexibility components (conflict-EF). In particular, child attachment security was related to conflict-EF performance at 3 years above and beyond what was explained by a combination of all other social antecedents of child EF identified thus far: child verbal ability and prior EF, family SES, and parenting behavior. Attachment security may thus play a meaningful role in young children's development of executive control.  相似文献   
920.
To investigate individual differences in creativity as measured with a complex problem-solving task, we developed a computational model of the remote associates test (RAT). For 50 years, the RAT has been used to measure creativity. Each RAT question presents three cue words that are linked by a fourth word, which is the correct answer. We hypothesized that individuals perform poorly on the RAT when they are biased to consider high-frequency candidate answers. To assess this hypothesis, we tested individuals with 48 RAT questions and required speeded responding to encourage guessing. Results supported our hypothesis. We generated a norm-based model of the RAT using a high-dimensional semantic space, and this model accurately identified correct answers. A frequency-biased model that included different levels of bias for high-frequency candidate answers explained variance for both correct and incorrect responses. Providing new insight into the nature of creativity, the model explains why some RAT questions are more difficult than others, and why some people perform better than others on the RAT.  相似文献   
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