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941.
Juvenile budgerigars (Melopsittacus undulatus) observed thin film transistor video playback of a virtual conspecific demonstrator using its beak to remove a stopper from a food box, either by pulling the object upward or by pushing it downward. Simultaneously (Experiment 1) or subsequently (Experiment 2), the observers were offered a similar stopper box and rewarded with access to food for each removal response, regardless of its direction. Observers of upward movement made a greater proportion of up responses in total and showed a stronger tendency to increase the proportion of up responses over test trials than observers of downward movement. These findings provide the first demonstration of which the authors are aware that birds are able not only to detect and respond to a moving video image but also to copy its movements.  相似文献   
942.
Despite the prominence of the disability civil rights model--with its values of inclusion and empowerment--the majority of social and policy research conducted to date has not sufficiently included the perspective of persons with disabilities in the research process and as uniquely qualified researchers themselves. This article describes a new project, "Technology for Independence: A Community-Based Resource Center" (CBRC). Over a five-year period, the CBRC will attempt to enhance community and consumer-directed disability organizations to design, implement, and disseminate research that promotes access to and use of assistive technology (AT). The CBRC will use strategies such as leadership training, participatory action research, technical assistance, web-assisted training, and annual symposia. A primary goal of the CBRC is to increase the capacity of community organizations to conduct research on AT that is scientifically rigorous and relevant to disability services, policy, and law.  相似文献   
943.
The aim of this study was to assess interrater reliability and provide initial data bearing on the validity of a method of assessing personality disorders (PDs) that does not presume that patients can accurately self-report personality pathology. In a sample of 24 outpatients, two clinician-judges independently applied the Shedler-Westen Assessment Procedure-200 (SWAP-200; Westen & Shedler, 1999a, 2000), a 200-item Q-sort procedure for assessing personality pathology, to data from the Clinical Diagnostic Interview (Westen, 2002), a systematic clinical interview that mirrors and standardizes methods used by experienced clinicians to diagnose personality. In 16 of the 24 cases, the treating clinician also independently described the patient using the SWAP-200 Q-sort, based on longitudinal knowledge of the patient over the course of treatment, blind to the interview data. Interrater reliability was uniformly high, with median correlations between interviewers at r > .80. Interviewer-treating clinician correlations were also high, with median convergent validity coefficients at r > .80. Diagnostic overlap (discriminant validity) was moderate for dimensional DSM-IV diagnoses, reflecting extensive comorbidity among disorders, but minimal for empirically derived diagnoses identified in prior research. Treating clinicians' dimensional PD diagnoses using this method also strongly predicted interviewer-rated measures of adaptive functioning. The findings provide preliminary support for the reliability and validity of an alternative to structured interviews for diagnosing personality pathology, and suggest that the way to improve validity of personality diagnosis may not be to minimize clinical inference but to quantify it using psychometric instruments.  相似文献   
944.
The authors investigated whether expertise is more likely to mitigate age declines when experts rely on environmental support in a pilot/Air Traffic Control (ATC) communication task. Pilots and nonpilots listened to ATC messages that described a route through an airspace, while they referred to a chart of the airspace. They read back (repeated) each message and then answered a probe question about the route. In a preliminary study, participants could take notes while listening to the messages and performing the read-back and probe tasks. In Experiment 1, opportunity to take notes was manipulated. Note taking determined when expertise mitigated age differences on the read-back task. With note taking, read-back accuracy declined with age for nonpilots but not for pilots. Without note taking, similar age-related declines occurred for pilots and nonpilots. Benefits of expertise, younger age, and note taking occurred for probe accuracy, but mitigation did not occur. The findings suggest that older adults take advantage of a domain-relevant form of environmental support (note taking) to maintain performance on some complex tasks despite typical age-related declines in cognitive ability.  相似文献   
945.
Beyond keeping active: concomitants of being a volunteer in old-old age   总被引:4,自引:0,他引:4  
This study examines concomitants of volunteering in the context of other lifestyle activities. Investigating formal volunteering in old-old age, the authors analyzed data of 148 volunteers versus 1,195 nonvolunteers in a national sample of the Israeli Jewish population aged 75-94. As hypothesized, being a volunteer related (whether as a cause or effect) to more positive functioning on psychosocial markers and prospectively resulted in reduced mortality risk even when other activity outlets (physical activity, everyday activities, having a hobby) were controlled. These findings suggest that the benefits of volunteering in late life are not reducible to those of other activities.  相似文献   
946.
Hindsight bias is the tendency of people to falsely believe that they would have correctly predicted the outcome of an event once it is known. The present paper addresses the ongoing debate as to whether the hindsight bias is due to memory impairment or biased reconstruction. The memory impairment approach maintains that outcome information alters the memory trace of the initial judgement, whereas the biased reconstruction approach assumes that people who have forgotten their initial judgements are forced to guess and, in the presence of outcome information, are likely to use this information as an anchor. Whereas the latter approach emphasises the role of meta-cognitive considerations, meta-cognitions are not included in the memory impairment explanation. Two experiments show that the biased reconstruction approach provides a better explanation for empirical findings in hindsight bias research than does the memory impairment explanation.  相似文献   
947.
Effects of experience on fetal voice recognition   总被引:1,自引:0,他引:1  
Abstract - The ability of human fetuses to recognize their own mother's voice was examined. Sixty term fetuses were assigned to one of two conditions during which they were exposed to a tape recording of their mother or a female stranger reading a passage. Voice stimuli were delivered through a loudspeaker held approximately 10 cm above the maternal abdomen and played at an average of 95 dB SPL. Each condition consisted of three 2-min periods: no stimulus, voice (mother or stranger), and no stimulus. Fetal heart rate increased in response to the mother's voice and decreased in response to the stranger's; both responses were sustained for 4 min. The finding of differential behavior in response to a familiar versus a novel voice provides evidence that experience influences fetal voice processing. It supports an epigenetic model of speech perception, presuming an interaction between genetic expression of neural development and species-specific experience.  相似文献   
948.
Sit-and-wait strategies in dynamic visual search   总被引:1,自引:0,他引:1  
The role of memory in visual search has lately become a controversial issue. Horowitz and Wolfe (1998) observed that performance in a visual search task was little affected by whether the stimuli were static or randomly relocated every 111 ms. Because a memory-based mechanism, such as inhibition of return, would be of no use in the dynamic condition, Horowitz and Wolfe concluded that memory is likewise not involved in the static condition. However, Horowitz and Wolfe could not effectively rule out the possibility that observers adopted a different strategy in the dynamic condition than in the static condition. That is, in the dynamic condition observers may have attended to a subregion of the display and waited for the target to appear there (sit-and-wait strategy). This hypothesis is supported by experimental data showing that performance in their dynamic condition does not differ from performance in another dynamic condition in which observers are forced to adopt a sit-and-wait strategy by being presented with a limited region of the display only.  相似文献   
949.
Attribution of dispositional states by 12-month-olds   总被引:4,自引:0,他引:4  
The ability to interpret the behavior of other individuals is essential for effective social functioning. Many investigators now believe that even young infants can recognize that agents act toward goals. Here we report three experiments suggesting that 12-month-old infants not only can recognize goal-related action, but also can interpret future actions of an actor on the basis of previously witnessed behavior in another context. The possibility that this inference is made through the attribution of mental states is discussed.  相似文献   
950.
This study inspected the deterministic structure of unipolar depression. Two women self-monitored sadness hourly 10 times a day for 6 months. One woman had a recurrent history of unipolar depression, and the other did not. Data were analyzed by visual inspection, examination of the Fourier transforms of the time plots, and the correlation dimension. Results suggested that in addition to a strong periodic component that existed only within the depressed subject's mood time series, a low-dimensional chaotic process might have been operating. In the nondepressed control subject, no such periodicity or process could be identified. The findings support maladaptive deterministic theories of mood disorders and have implications for the assessment of unipolar depression.  相似文献   
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