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881.
882.
Two experiments tested if cognitive load interferes with perspective-taking in verbal communication even if feedback from the addressee is available. Participants gave instructions on the assembly of a machine model. In Experiment 1, cognitive load was demonstrated to be a function of the complexity of assembly steps. In Experiment 2, position of feedback (during simple vs. during complex steps) and type of feedback (question vs. ambiguous interjection) were manipulated. With simple steps, speakers' responses were a function of feedback type. Speakers responded differently to questions than to interjections. With complex steps, however, responses were a function of cognitive load. Regardless of the type of feedback, most speakers simply repeated their previous utterances.  相似文献   
883.
The influence of interindividual differences in cognitive mechanisms on language comprehension remains controversial not only due to conflicting experimental findings, but also in view of the difficulty associated with determining which measure should be used in participant classification. Here, we address the latter problem by proposing that an electrophysiological measure, individual alpha frequency (IAF), may be a suitable means of classifying interindividual differences in sentence processing. Interindividual differences in IAF have been shown to correlate with performance on memory tasks and speed of information processing. In two experiments using event-related brain potentials (ERPs), IAF-based participant groups differed systematically with regard to the processing of ambiguous sentences such that the low-IAF group showed a sustained positivity in the ambiguous region, while the high-IAF group did not. These interindividual differences were independent of whether the ambiguity was syntactic (Experiment 1) or sentence-level semantic (Experiment 2). Moreover, they were reliable only when participants were classified according to IAF, but not in classifications based on reading span, speed of processing (reaction time), or accuracy of processing (error rate).  相似文献   
884.
We examined the role of motor affordances of objects for working memory retention processes. Three experiments are reported in which participants passively viewed pictures of real world objects or had to retain the objects in working memory for a comparison with an S2 stimulus. Brain activation was recorded by means of functional magnetic resonance imaging (fMRI). Retaining information about objects for which hand actions could easily be retrieved (manipulable objects) in working memory activated the hand region of the ventral premotor cortex (PMC) contralateral to the dominant hand. Conversely, nonmanipulable objects activated the left inferior frontal gyrus. This suggests that working memory for objects with motor affordance is based on motor programs associated with their use. An additional study revealed that motor program activation can be modulated by task demands: Holding manipulable objects in working memory for an upcoming motor comparison task was associated with left ventral PMC activation. However, retaining the same objects for a subsequent size comparison task led to activation in posterior brain regions. This suggests that the activation of hand motor programs are under top down control. By this they can flexibly be adapted to various task demands. It is argued that hand motor programs may serve a similar working memory function as speech motor programs for verbalizable working memory contents, and that the premotor system mediates the temporal integration of motor representations with other task-relevant representations in support of goal oriented behavior.  相似文献   
885.
We developed a Web-based intervention for pediatric traumatic brain injury (TBI) and examined its feasibility for participants with limited computer experience. Six families, including parents, siblings, and children with TBI, were given computers, Web cameras, and high-speed Internet access. Weekly videoconferences with the therapist were conducted after participants completed on-line interactive experiences on problem solving, communication, and TBI-specific behavior management. Families were assigned to videoconference with NetMeeting (iBOT cameras) or ViaVideo. Participants ranked the Web site and videoconferences as moderately to very easy to use. ViaVideo participants rated videoconferencing significantly more favorably relative to face-to-face meetings than did NetMeeting participants. Both the Web site and videoconferencing were rated as very helpful. All families demonstrated improved outcomes on one or more target behaviors, including increased understanding of the injury and improved parent-child relationships. All parents and siblings and all but 1 child with TBI said they would recommend the program to others. We conclude that a face-to-face intervention can be successfully adapted to the Web for families with varied computer experience.  相似文献   
886.
We describe a new, open flow device for presenting taste stimuli to human subjects under controlled conditions of timing. The device delivers each stimulus as a mist to the participant’s tongue through one of 16 nozzles attached to a linear slide. Software controls the position of the slide, the duration of the stimulus, and the duration of the pre- and poststimulus water rinses and records the responses of the participant. Temporal characteristics of this system make it especially applicable to studies on the role of attention in taste perception.  相似文献   
887.
Pole M  Crowther JH  Schell J 《Body image》2004,1(3):267-278
Family factors and the media have been established as determinants of body satisfaction, yet little research has looked at the contribution of spousal influence in body dissatisfaction. Marital quality and satisfaction can be a protective factor in the health of women, while high rates of criticism have been associated with poorer health outcomes. The present study investigated the relationship between perceptions of family and spousal factors and body dissatisfaction in married women. Additionally, the impact of marital communication was investigated. Seventy-seven married women completed self-report questionnaires assessing familial body-focused comments, spousal evaluation of a wife’s body, marital communication patterns, and body dissatisfaction. After controlling for weight status, women’s perceptions of familial body-focused comments and spousal evaluation emerged as significant predictors of body dissatisfaction. It was also found that more destructive communication patterns moderated the effect of perceived spousal evaluation on body dissatisfaction. This study provides some context for understanding the impact of specific influences on women’s body dissatisfaction.  相似文献   
888.
Rather than viewing anxiety among chronic pain patients as simply a component of negative affectivity, investigators have developed a model of "pain anxiety" in which patients develop fear and avoidance of activity linked to pain. We examined whether pain anxiety can be conceptualized as a specific phobia, or whether evidence supported the notion that pain anxiety is better understood as a manifestation of anxiety sensitivity in the context of chronic pain. Chronic musculoskeletal pain patients (N=70) underwent cold pressor and mental arithmetic tasks while cardiovascular, self-report, and behavior indexes were recorded. They completed measures of pain anxiety, anxiety sensitivity, fear of negative evaluation, depression and trait anxiety. Correlation analyses showed pain anxiety was related to pain-relevant responses during cold pressor, but it was also related to evaluation-relevant responses during cold pressor, and to pain- and evaluation-relevant responses (including subtraction accuracy) during mental arithmetic. Regression analyses showed that almost all effects of pain anxiety on task responses were accounted for by anxiety sensitivity. Fear of negative evaluation, in contrast, correlated only with evaluation-relevant responses, and mostly during mental arithmetic. These effects remained significant when depression, trait anxiety, or anxiety sensitivity were statistically controlled. Pain anxiety may be an expression of anxiety sensitivity rather than a circumscribed phobia; a distinction that could profitably guide treatment strategies.  相似文献   
889.
Withdrawal symptoms following cessation of heavy cannabis (marijuana) use have been reported, yet their time course and clinical importance have not been established. A 50-day outpatient study assessed 18 marijuana users during a 5-day smoking-as-usual phase followed by a 45-day abstinence phase. Parallel assessment of 12 ex-users was obtained. A withdrawal pattern was observed for aggression, anger, anxiety, decreased appetite, decreased body weight, irritability, restlessness, shakiness, sleep problems, and stomach pain. Onset typically occurred between Days 1-3, peak effects between Days 2-6, and most effects lasted 4-14 days. The magnitude and time course of these effects appeared comparable to tobacco and other withdrawal syndromes. These effects likely contribute to the development of dependence and difficulty stopping use. Criteria for cannabis withdrawal are proposed.  相似文献   
890.
Latent growth models were applied to data from the Swedish Adoption/Twin Study of Aging to discover if the rate of change in cognitive performance increased from middle age to later adulthood. The sample included 590 participants aged 44 to 88 years at first measurement. Data were gathered at 2 follow-up occasions at intervals of 3 years. Cognitive ability was assessed through 11 tests that tapped crystallized, fluid, memory, and spatial abilities and perceptual speed. Results indicated stability for measures of crystallized ability, linear age changes for many cognitive abilities, and a significant acceleration in linear decline after age 65 for measures with a large speed component. Gender differences were found only in mean level, not in rate of decline.  相似文献   
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