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851.
Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced.  相似文献   
852.
Despite the crucial role typically given to negative thoughts in cognitive conceptualisations of emotional problems, few studies have compared the characteristics of varieties of such thoughts. The present study compared the process features of naturally occurring worries and obsessions in a non-patient group. Analyses of variance revealed several significant differences between these types of thought. The relationship between worries and obsessions, and the clinical and conceptual importance of the observed differences is briefly discussed.  相似文献   
853.
High-probability requests were used to increase social interactions in 3 young boys with severe disabilities who had been identified as severely socially withdrawn. A multiple baseline design across participants was used to evaluate the effects of high-probability request intervention on (a) social initiations, (b) social responses, (c) continued interactions, and (d) performance of high- and low-probability requests. The students were observed in a second setting to examine generalization effects across peers who did not participate in the training sequence and settings. The results demonstrated that the high-probability requests increased the students' responsiveness to low-probability requests to initiate social behavior. Increases were also found in (a) unprompted initiations and extended interactions to the training peers, (b) unprompted initiations and extended interactions to peers who were not involved in the training procedure, and (c) generalized unprompted initiations and interactions in a second nontraining setting. The students maintained increased levels of initiations and interactions after all prompts were removed from both the training and nontraining settings.  相似文献   
854.
In this study a social comparison model is constructed that predicts objectively recorded absence frequency among male Dutch blue-collar workers from a metal factory in the Netherlands. By employing LISREL, the model is developed (tested and revised) in Plant North (N = 254), and successfully cross-validated in Plant South (N= 199). The study demonstrates the impact of two social comparison processes upon absenteeism. Absenteeism is the result of: (a) the perception that one is less well-off than one's colleagues on several job aspects, and (b) the adjustment of one's personal absence norm to that of the work group. In addition, our study reveals that, rather than being absent or having tolerant absence norms, employees may develop feelings of resentment in response to perceived inequity and a tolerant group absence norm. It is concluded that social comparison theory enhances our understanding of absenteeism.  相似文献   
855.
A preference-based measure of responses to warning labels was used to study alternative alcohol warning labels that differed in: (a) length, (b) presence of qualifier words, (c) alternative content, and (d) specific beverage. The specific risks mentioned were more important than the overall label length, qualifier words reduced avoidance responses, various alternative warnings elicited more avoidance responses than the existing alcohol warning label, and more avoidance responses were made to labels on a whiskey bottle than on a beer bottle. Warnings with the words “poison,”“cancer,” or “health problems” were the most powerful. The results for college students in Study 1 were replicated in a high-school sample in Study 2.  相似文献   
856.
Attributional retraining appears to be an effective remedial intervention for college students. However, the potential moderating effects of student and classroom characteristics have not yet been investigated systematically. In two studies, attributional retraining was provided to low- and high-risk students, followed by a videotaped lecture presented by either an ineffective or effective instructor. Attributional retraining enhanced achievement on a lecture-based achievement test only when combined with effective teaching, improving the achievement of students who had previously performed poorly (Experiment l), and of low-achieving externals (Experiment 2). The intervention provided no advantage for previously successful students and low-achieving internals. Moreover, attributional retraining induced a more internal attribution profile in students with an external locus, and increased expectations of future success in both externals and internals, but again only when students also received effective instruction. These results suggest that contextual factors related to the classroom, such as quality of instruction, and individual differences have to be considered when developing attributional retraining programs.  相似文献   
857.
Four experiments were conducted to examine the effects of periodic visual occlusion on one-handed ball catching. Tennis balls were projected one at a time over distances of 8-12 m, and liquid-crystal visual occlusion spectacles provided intermittent vision by opening and closing the lens shutters at different frequencies. As well as frequency, we manipulated duty cycle, or the proportion of time that the lenses were open. Generally, catching performance deteriorated as frequency was reduced. Although longer visual samples (i.e., increased duty cycle) mediated this effect to some extent, the most potent variable was the time between visual samples; performance deteriorated rapidly when this interval was greater than 80 ms (i.e., 10 Hz with 20-ms lens open times). Presumably this occurred because subjects had difficulty integrating visual information separated by longer temporal intervals.  相似文献   
858.
Five experiments are reported in which the effect of partial visual feedback on the accuracy of discrete target aiming was investigated. Visual feedback was manipulated through a spectacle-mounted liquid-crystal tachistoscope. The length of the visual feedback interval was varied as a percentage of the instructed movement time. In Experiment 1, the length of the vision interval was manipulated symmetrically at the beginning- and end-phase of the movement, whereas in the remaining experiments, the vision time was varied with respect to the end-phase only. The variations at the end were examined for different distances (Experiment 2), different movement speeds at the same distance (Experiment 3), and in small interstep intervals (Experiment 4). A vision time of more than 150 ms at the end-phase of the movement enhanced aiming performance in all experiments. Longer vision times monotonously improved aiming accuracy; the fifth experiment showed that a vision time of about 275 ms was sufficient for near-perfect aiming. Furthermore, the significance of vision during the first phase of a movement was demonstrated again. The results of the five experiments pointed to shorter visuomotor processing times. To explain the beneficial effects of short vision times for aiming accuracy, we propose a model of visuomotor processing that is based on the stochastic optimized submovement model of Meyer, Abrams, Kornblum, Wright, and Smith (1988).  相似文献   
859.
A historical antagonism between proponents of qualitative methods and quantitative methods has prevented recognition of the benefits to be gained by employing both methods (that is, a multi-method approach) during the same study or program of studies. Increasingly, family therapy researchers have begun to recognize the value of a multi-method approach in bridging the current gaps among theory, research, and practice. However, current writings have yet to move beyond the discussion stage. This article proposes a bidirectional continuum that includes both qualitative and quantitative methods. An ethnographic content analysis approach is presented to illustrate the procedural stages of this continuum. The article ends with a discussion of the challenges in carrying out a bidirectional, multi-method approach and the potential contributions that an integrative research methodology will give both researchers and clinicians.  相似文献   
860.
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