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841.
Infants increasingly generalize deferred imitation across environmental contexts between 6 and 18 months of age. In three experiments with 126 6-, 9-, 12-, 15-, and 18-month-olds, we examined the role of the social context in deferred imitation. One experimenter demonstrated target actions on a hand puppet, and a second experimenter tested imitation 24h later. When the second experimenter was novel, infants did not exhibit deferred imitation at any age; when infants were preexposed to the second experimenter, all of them did. Imitating immediately after the demonstration also facilitated deferred imitation in a novel social context at all ages but 6 months. Infants' pervasive failure to exhibit deferred imitation in a novel social context may reflect evolutionary selection pressures that favored conservative behavior in social animals.  相似文献   
842.
R. Ivry, R. M. Spencer, H. N. Zelaznik, and J. Diedrichsen (2002) have proposed a distinction between timed movements in which a temporal representation is part of the task goal (event timing) and those in which timing properties are emergent. The issue addressed in the present experiment was how timing in conditions conducive to emergent timing becomes established. According to what the authors term the transformation hypothesis, timing initially requires an event-based representation when the temporal goal is defined externally (e.g., by a metronome), but over the first few movement cycles, control processes become established that allow timing to become emergent. Different groups of participants (N = 84) executed either 1 timed interval, 4 timed intervals, or 2 timed intervals separated by a pause. They produced the intervals by either circle drawing, a task associated with emergent timing, or tapping, a task associated with event timing. Analyses of movement variability suggested that similar timing processes were used in the 2 tasks only during the 1st interval. Those results are consistent with the transformation hypothesis and lead to the inference that the transition from event-based control to emergent timing can occur rapidly during continuous movements.  相似文献   
843.
The authors sought to gain further knowledge about activation of target muscles during imagery engagement in a motor task. Six hemiparetic patients and 9 healthy participants performed 3 real rises on tiptoes and then, after pausing, 3 imagery rises on tiptoes. Metronome beats guided the rate of rises and descents. Electromyographic (EMG) activity from the medial gastrocnemius and the rectus femoris muscles were monitored bilaterally throughout the performance of both tasks. In 3 healthy participants and 3 individuals with hemiparesis, EMG activity was related to the imagery task in at least 1 of the target muscles. Conversely, in the other participants, motor imagery practice was not accompanied by task-related EMG activity in the monitored muscles. In all cases, the increment in activation level during motor imagery practice was very low in comparison with that of real performance. The findings were not unequivocal; therefore, EMG activity may sometimes, but not always, be recorded during motor imagery practice both in healthy individuals and in poststroke hemiparetic participants. Further research is needed to align motor imagery practice with the objectives of motor rehabilitation.  相似文献   
844.
The authors investigated whether the salience of dynamic visual information in a video-aiming task mediates the specificity of practice. Thirty participants practiced video-aiming movements in a full-vision, a weak-vision, or a target-only condition before being transferred to the target-only condition without knowledge of results. The full- and weak-vision conditions resulted in less endpoint bias and variability in acquisition than did the target-only condition. Going from acquisition to transfer resulted in a large increase in endpoint variability for the full-vision group but not for the weak-vision or target-only groups. Kinematic analysis revealed that weak dynamic visual cues do not mask the processing of other sources of afferent information; unlike strong visual cues, weak visual cues help individuals calibrate less salient sources of afferent information, such as proprioception.  相似文献   
845.
The authors examined self-enhancing bias as a predictor of adjustment among individuals in or near the World Trade Center during the September 11, 2001, terrorist attacks. Resilience was defined from categorical and continuous analyses of both participant self-report and friend and relative ratings of adjustment. Self-enhancement was associated with a resilient outcome, ratings of better adjustment prior to September 11th, greater positive affect, and reduced perceptions of social constraints. Additional analyses indicated that self-enhancers' reduced symptom levels were fully mediated by their low perceived social constraints. However, consistent with previous evidence suggesting a social cost to self-enhancement, at 18 months post-September 11th, self-enhancers' friends and relatives also rated them as decreasing in social adjustment and as being less honest.  相似文献   
846.
Recent research has revealed that nonconscious activation of desired behavioral states--or behavioral goals--promotes motivational activity to accomplish these states. Six studies demonstrate that this nonconscious operation of behavioral goals emerges if mental representations of specific behavioral states are associated with positive affect. In an evaluative-conditioning paradigm, unobtrusive linking of behavioral states to positive, as compared with neutral or negative, affect increased participants' wanting to accomplish these states. Furthermore, participants worked harder on tasks that were instrumental in attaining behavioral states when these states were implicitly linked to positive affect, thereby mimicking the effects on motivational behavior of preexisting individual wanting and explicit goal instructions to attain the states. Together, these results suggest that positive affect plays a key role in nonconscious goal pursuit. Implications for behavior-priming research are discussed.  相似文献   
847.
It is proposed that personality (conceptualized in terms of motives and psychological resources) changes normatively not only from young adulthood to middle age but also within middle age and that these changes take place in relation to social and biosocial change over the same period. Data from 123 women studied at ages 27, 43, 52, and 61 largely supported hypotheses about change in social roles, status, health, motives, personality characteristics, emotion regulation, and relationships. Noteworthy aspects of the findings were substantial curvilinear change within middle age and associations of work involvement and physical health with personality change during late middle age.  相似文献   
848.
In 4 studies, the authors investigated the relative impact of biased encoding of information and communication goals on biased language use. A category label (linguistic expectancy bias, Study 1) or a group label (linguistic intergroup bias, Study 2) was presented either before or after a story that participants were asked to communicate. Biased language use only emerged when participants learned about the group membership of the actor or the category label before hearing the story. However, communication goals had an effect on language use at the retrieval stage, independent of encoding (Studies 3 and 4). Although communication goal effects seemed to overwhelm encoding effects, encoding still influenced language use under externally imposed time pressure (Study 3) and self-imposed time constraints (Study 4). This research reaffirms the importance of both cognitive and communicative processes in stereotype maintenance and highlights the conditions under which they each operate.  相似文献   
849.
In two studies, we examined the role of perceived fulfillment of parental expectations in the subjective well-being of college students. In Study 1, we found that American college students reported having higher levels of life satisfaction and self-esteem than did Japanese college students. American college students also reported having fulfilled parental expectations to a greater degree than did Japanese college students. Most importantly, the cultural difference in well-being was mediated by perceived fulfillment of parental expectations. In Study 2, we replicated the mediational finding with Asian American and European American college students. Asian American participants also perceived their parents' expectations about their academic performance to be more specific than did European Americans, which was associated with the cultural difference in perceived fulfillment of parental expectations. In short, perceived parental expectations play an important role in the cultural difference in the well-being of Asians and European Americans.  相似文献   
850.
Personality and social relationships play an important role in almost every aspect of stress and coping. Daily process methods are particularly useful in elucidating how these factors might influence both responses to and outcomes of stress. Our work has linked both dimensions of personality, particularly the Big Five, and aspects of social relationships, particularly social support, to the likelihood of engaging in certain coping strategies and the effectiveness or outcomes of these coping strategies. In addition, we have found the effect of personality on coping and stress outcomes to vary by the situational context in which stress occurs. We review findings from our recent daily process studies of stress, coping, and social support. Further, we discuss the costs and benefits of the daily process methodology for addressing these questions, highlighting the clinical utility of findings gleaned with the use of this approach. Finally, we discuss future directions and applications of daily process methods to the study of stress and coping.  相似文献   
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