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121.
We distinguish between the roles played by spatial attention and conscious intention in terms of their impact on the processing of segmentation signals, like discontinuities in lines, associated with the act of scrutinizing. We showed previously that the processing of discontinuities in lines can be activated. This is evidenced by an impairment in the detection of a gap between parallel elements when it follows a gap between collinear elements in the same location and orientation. This effect is no longer observed if attention is divided between two gaps in the first stimulus. The results from this study show that focusing attention on a gap between collinear elements is not enough to observe a modulation, consistently with the need to integrate, rather than to separate, collinear elements in usual conditions. The modulation is sensitive to the conscious expectations of subjects, suggesting that an intention can trigger modulations that spatial attention cannot.  相似文献   
122.
Three experiments assessed whether capuchin monkeys (Cebus apella) and squirrel monkeys (Saimiri sciureus) prefer regular and symmetrical visual patterns. Pictorial representations of faces were included in 1 stimulus set. When the monkeys could pick up and manipulate small cards bearing the stimuli, all preferences expressed by capuchins and most of those expressed by squirrel monkeys were for regular stimuli. Symmetry of the patterns was influential but not essential. Some preferences were also found for faces. When images of the patterns were presented on a touch screen, capuchins continued to express preferences especially for regular and symmetrical stimuli, but they showed some avoidance of faces. Squirrel monkeys responded less discriminatingly to the touch screen stimuli. The findings provide support for B. Rensch's (1957) claim that monkeys prefer visual stimuli that humans find aesthetically pleasing.  相似文献   
123.
Capuchin monkeys (Cebus apella) matched a variety of rodlike figures, distinguishable only by their central portions. The monkeys were then tested for perceptual completion rules by examining which comparison figures they would choose as matching the sample with the critical central portion occluded by a horizontal belt. In Experiment 1, the monkeys overwhelmingly chose a straight rod over disconnected rods and rods having irregular shapes at their center, irrespective of the presence-absence of common motion of visible parts of the samples. The monkeys chose a connected rod for relatable rods and disconnected rods for non-relatable ones in Experiment 2. In Experiments 3 and 4, some of the monkeys chose rods specified by the global regularity of the contour, whereas others did not. Experiment 5 showed that humans and capuchin monkeys basically follow similar perceptual rules in completing occluded contours, but the global regularity rule may be stronger in humans.  相似文献   
124.
Humans and pigeons were trained to discriminate between 2 views of actual 3-D objects or their photographs. They were tested on novel views that were either within the closest rotational distance between the training views (interpolated) or outside of that range (extrapolated). When training views were 60 degrees apart, pigeons, but not humans, recognized novel views of actual objects better than their pictures. Further, both species recognized interpolated views of both stimulus types better than extrapolated views, but a single distinctive geon enhanced recognition of novel views only for humans. When training views were 90 degrees apart, pigeons recognized interpolated views better than extrapolated views with actual objects but not with photographs. Thus, pigeons may represent actual objects differently than their pictures.  相似文献   
125.
Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was invalidly cued were significantly higher for the group with dyslexia, while costs associated with shifts toward the fovea tended to be lower. Higher costs were also shown by the group with dyslexia for up-down shifts of attention in the periphery. A visual field processing difference was found, in that the group with dyslexia showed higher costs associated with shifting attention between objects in they LVF. These findings indicate that these adults with dyslexia have difficulty in both the space-based and the object-based components of covert visual attention, and more specifically to stimuli located in the periphery.  相似文献   
126.
The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders.  相似文献   
127.
This multicenter study aimed to assess (i) whether individual clinical geneticists and genetic counselors vary in their communication skills and (ii) whether this variation in communication impacts on patient outcomes, such as anxiety, depression, genetics knowledge, and satisfaction. One hundred and fifty women from high-risk breast cancer families attending their first genetic counseling consultation completed pre and post-consultation self-report questionnaires. The consultations were audiotaped and transcribed verbatim. Univariate analyses showed highly significant differences between individual clinical geneticists and genetic counselors in: facilitating understanding (p 0.001); facilitating active involvement (p 0.001); facilitating partnership building (p = 0.003); addressing emotional concerns (p 0.001); and discussing prophylactic mastectomy (p = 0.017). Multivariate linear regressions showed that this variation in communication resulted in a greater change in patients depression 4 weeks after the counseling session (p = 0.017). These findings suggest clinical geneticists and genetic counselors have achieved some standardization in communicating information, but showed diversity in their facilitation skills. Communication skills may be a useful area to explore further in this field.  相似文献   
128.
Infants' sensitivity to social contingencies was assessed. In Study 1, 1-month-old infants and their mothers interacted face-to-face in three types of imperfect contingent interactions: Normal, Non-Contingent and Imitation. One-month-old infants did not discriminate these conditions. In Study 2, 3-month-old infants were tested as in Study 1. At 3 months of age, infants gazed reliably longer in the Imitation condition and smiled reliably more in the Normal than in the Non-Contingent and Imitation interactions. These findings suggest a developmental transition in the sensitivity to social contingencies between 1 and 3 months of age. The relationship between the developing sensitivity to social contingencies and social cognition is discussed.  相似文献   
129.
This article examines the theoretical basis of decision-making deficits exhibited by cocaine abusers in a laboratory decision-making task first described by Bechara, Damasio, Damasio, and Anderson (1994). A total of 12 male cocaine abusers and 14 comparison subjects performed the task, and the cocaine group performed significantly worse than the comparison group. A cognitive modeling analysis (Busemeyer & Stout, 2002) was used to estimate three parameters that measure importance of the cognitive, motivational, and response processes for determining the observed performance deficit. The results of this analysis indicated, for the first time, that motivational and choice consistency factors, but not learning/ memory were mainly responsible for the decision-making deficit of the cocaine abusers in this task.  相似文献   
130.
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.  相似文献   
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