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881.
The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.  相似文献   
882.
Stimulus identification and action outcome understanding for a rapid and accurate response selection, play a fundamental role in racquet sports. Here, we investigated the neurodynamics of visual anticipation in tennis manipulating the postural and kinematic information associated with the body of opponents by means of a spatial occlusion protocol. Event Related Potentials (ERPs) were evaluated in two groups of professional tennis players (N = 37) with different levels of expertise, while they observed pictures of opponents and predicted the landing position as fast and accurately as possible. The observed action was manipulated by deleting different body districts of the opponent (legs, ball, racket and arm, trunk). Full body image (no occlusion) was used as control condition. The worst accuracy and the slowest response time were observed in the occlusion of trunk and ball. The former was associated with a reduced amplitude of the ERP components likely linked to body processing (the N1 in the right hemisphere) and visual-motor integration awareness (the pP1), as well as with an increase of the late frontal negativity (the pN2), possibly reflecting an effort by the insula to recover and/or complete the most correct sensory-motor representation. In both occlusions, a decrease in the pP2 may reflect an impairment of decisional processes upon action execution following sensory evidence accumulation. Enhanced amplitude of the P3 and the pN2 components were found in more experienced players, suggesting a greater allocation of resources in the process connecting sensory encoding and response execution, and sensory-motor representation.  相似文献   
883.
ObjectiveLatent class modeling (LCM) offers a promising approach for examining correlates of heart rate (HR) patterns over multiple exercise sessions. This research examined biological and psychological variables associated with different patterns of HR response to physical activity (PA).MethodsIn a three-arm randomized controlled trial (exercise video games vs. standard exercise vs. non-exercise control), HR was recorded during PA sessions over a 12-week period. LCM identified three patterns of HR during PA across 189 participants in active arms: 1) high HR across sessions with low variability within sessions, 2) linear increase in HR across sessions with low variability within sessions, and 3) high variability in HR across all sessions. Associations with biological (resting heart rate, blood pressure, BMI, age, cholesterol, triglycerides, HbA1c) and psychological (depression, motivations for PA, PA-induced feelings) predictors of latent class membership were iteratively tested.ResultsPsychological variables played as important a role in the final model as biological variables for predicting latent class membership. Few differences were found between LC1 and LC2, but LC3 differed from the other two groups in that participants were likelier to report that they feel revitalized after PA (vs. LC1 and LC2), to be less motivated for PA (vs. LC1), reported greater depression (vs. LC1 and LC2), and were younger (vs. LC1).ConclusionsThese findings demonstrate the potential of LCM to identify biological and psychological factors associated with chronotropic responses to PA, and advance understanding of the role of psychological factors in chronotropic PA outcomes.  相似文献   
884.
Kuhlmann''s Living Walden Two (2005) offers a social history of the actual experimental communities that were inspired by Skinner''s (1948) utopian novel. In the course of her examination, the author presents a reasonably accurate overview of the key cultural design elements described in the novel, of behavioral philosophy applied to cultural design, and of the academic reaction to the behavioral philosophy embodied in the fictional community. She is critical of several key behavioral tenets, but generally remains analytical rather than emotional. Kuhlmann concludes that contextual and individual factors undermined the capacity of most of the experimental communities inspired by Walden Two to sustain themselves.  相似文献   
885.
The educational and counseling models are often touted as the two primary professional approaches to genetic counseling practice. Yet, research has not been conducted to examine how these approaches are used in practice. In the present study, we conducted quantitative communication analyses of BRCA1 genetic counseling sessions. We measured communication variables that represent content (e.g., a biomedical focus) and process (e.g., passive listening) to explore whether genetic counselor approaches are consistent with prevailing professional models. The Roter Interaction Analysis System (RIAS) was used to code 167 pre-test genetic counseling sessions of members of a large kindred with an identified BRCA1 mutation. Three experienced genetic counselors conducted the sessions. Creating composite categories from the RIAS codes, we found the sessions to be largely educational in nature with the counselors and clients devoting the majority of their dialogue to providing biomedical information (62 and 40%, respectively). We used cluster analytic techniques, entering the composite communication variables and identified four patterns of session communication: Client-focused psychosocial, biomedical question and answer, counselor-driven psychosocial, and client-focused biomedical. Moreover, we found that the counselors had unique styles in which they combined the use of education and counseling approaches. We discuss the importance of understanding the variation in counselor communication to advance the field and expand prevailing assumptions.  相似文献   
886.
Yamada J 《Cognition》2004,93(2):127-32; discussion 133-7
Do different L1 (first language) writing systems differentially affect word identification in English as a second language (ESL)? Wang, Koda, and Perfetti [Cognition 87 (2003) 129] answered yes by examining Chinese students with a logographic L1 background and Korean students with an alphabetic L1 background for their phonological and orthographic processing skills on English word identification. Such a conclusion is premature, however. We propose that the L1 phonological system (rather than the L1 writing system) of the learner largely accounts for cognitive processes in learning to read a second language (L2).  相似文献   
887.
This paper offers a case study of the origins, emergence, and evolution of the term cumulative record as the name for the means by which B. F. Skinner brought his behavior under the control of his subject matter. Our methods included on-line searches, reviews of Skinner's publications, and journal codings and counts. The results reveal that the term is not originally attributable to Skinner, but emerged earlier in ordinary language and in another discipline--education. It was not even original to Skinner in print in his own science. Still, the term was once original to him, which we address with additional analyses of his having originated and advanced it. We conclude with a discussion the constraints of our methods, suggestions for future research, and the variable appreciation of technology and terminology in science studies.  相似文献   
888.
This 2-year study examined the effects of early second language exposure on phonological awareness skills. Syllable, onset-rime and phoneme awareness skills of 72 anglophone children attending English or French immersion programs in primary and grade 1 were investigated. Three-way mixed ANOVAS revealed the following effects and interactions. In terms of grade effect, grade 1 students performed significantly better than primary students on phoneme and onset-rime tasks. A stimulus language effect was observed for the three levels of phonological awareness. All children performed better on English tasks than on French ones. Interaction effects of stimulus language by program were revealed for phoneme as well as syllable tasks. Posthoc analyses revealed that French students performed better on English phoneme and syllable tasks than on French, while English students performed better than French immersion students on French syllable tasks. Correlational analyses revealed significant relationships between reading and phoneme and onset-rime phonological awareness tasks regardless of program of instruction (English, French immersion) or language of reading test (English, French). Syllable awareness was only significantly correlated with the French non-word reading task for the French immersion students.  相似文献   
889.
Background: Women who experience intimate partner violence (IPV) report greater stress and negative health consequences than nonabused women. Although an association between psychological stress and altered immune function has been shown, IPV studies have not investigated this relationship. Objective: This study explored the association of IPV with mental health symptoms and an immune marker to determine if posttraumatic stress disorder (PTSD) symptoms mediate the effect of IPV on pro-inflammatory (IFN-γ) cytokine levels. Methods: A cross-sectional, comparative design was used to compare 62 women with IPV and 39 nonabused women. Results: Mean IFN-γ values were higher in abused women and in women with current PTSD symptoms. There were no significant relationships with potential confounding variables that could provide an alternative explanation for the increase in production of proinflammatory cytokines. Conclusions: PTSD symptoms mediate the association between IPV and IFN-γ levels and may partially explain the association of mental health symptoms with physical health sequelae in IPV.  相似文献   
890.
Dose-dependent changes in sensitivity to reinforcement were found when rats were treated with low, moderate, and high doses of the partial dopamine D1-type receptor agonist SKF38393 and with the nonselective dopamine agonist apomorphine, but did not change when rats were treated with similar doses of the selective dopamine D2-type receptor agonist quinpirole. Estimates of bias did not differ significantly across exposure to SKF38393 or quinpirole, but did change significantly at the high dose of apomorphine. Estimates of goodness of fit (r2) did not change significantly during quinpirole exposure. Poor goodness of fit was obtained for the high doses of SKF38393 and apomorphine. Decrements in absolute rates of responding were observed at the high dose of quinpirole and at the moderate and high doses of SKF38393 and apomorphine. Changes in r2 and absolute responding may be due to increases in stereotyped behavior during SKF38393 and apomorphine exposure that, in contrast to quinpirole, were distant from the response lever. The present data provide evidence that sensitivity to reward is affected more strongly by dopamine D1-like receptors rather than D2-like receptors, consistent with evidence from other studies investigating consummatory dopamine behavior and the tonic/phasic dopamine hypothesis.  相似文献   
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