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971.
The Slade model for development of anorexia nervosa proposes that the female may seek success and control in her life by pursuing a thin body through dieting when faced with serious personal problems. Extending upon this model, the present program of research has sought to identify those characteristics of women generally at-risk for anorexia nervosa that would make dieting behavior especially successful, permitting the progression from food restraint into food aversion. The present studies considered whether heightened and stress-related inner stimulation could interfere with the at-risk woman's sensitivity to hunger sensations, thereby decreasing her motivation to eat. A series of analyses conducted within two studies indicated: (1) a relationship between elevated daily stress, concern over being over-whelmed by inner feelings, and a loss of discrimination regarding sources of inner feelings, (2) a tendency to narrow attentional focus when overloaded with excessive internal stimulation, and (3) diminished sensitivity to hunger sensations for women generally at-risk for anorexia nervosa given a narrowed attentional focus.  相似文献   
972.
Only few attempts have been made to compare different methods aiming at quantifying defensive strategies. In this study the tachistoscopic Defence Mechanism Test (Kragh, 1960b and 1985) is compared to paper-and-pencil tests of defence. There were virtually no correlations between the DMT and the other measures of defence. This may indicate that the concept of defence is a highly complex one. It is suggested that the Defence Mechanism Test may be measuring primary defence while defence questionnaires may be assessing more secondary forms of defence. The two questionnaires used for assessing defence correlated significantly, while a scale for social desirability showed no correlation with DMT or the two defence questionnaires.  相似文献   
973.
The goal of the reported experiment was to study how adults judge the meaning of different kinds of smiling and laughing by preschool children, and the role played by other facial movements in determining this meaning. Videotapes and photographs of spontaneous facial expressions of children in a play situation served as stimuli. The results show that different kinds of smiling were judged by the adult subjects as being significantly different from each other. In order to find subgroups within the stimuli, cluster analyses were performed, and the resulting clusters indicated different mixtures of positive and negative emotions contained within the pictures. Regression analyses showed that the adults' judgements were dependent on the number of indicators for positive and negative emotions which could be seen in the pictures. The most important indicator movement for the judged strength of the positive emotion expressed in the smile was the raising of the cheeks and, for negative emotions, the lowering of the lip corners. The significance of the components of the expressions as well as the strength of the expressed emotion were, however, dependent on the mode of presentation (video/photo).  相似文献   
974.
Converging operations on a basic level in event taxonomies   总被引:1,自引:0,他引:1  
Research on object concepts has identified one level of abstraction as "basic" in cognition and communication. We investigated whether concepts for routine social events have a basic level by replicating the converging operations used to investigate object concepts. In Experiment 1, subjects were presented with event names from a taxonomy and were asked to list the actions comprising the event. Many more actions were listed at the middle than at the highest taxonomic level, without a further increase at the most specific level, paralleling the pattern of superordinate-, basic-, and subordinate-level object concepts. From these action lists, brief stories were composed for each event. In Experiment 2, subjects made pairwise similarity judgments on the stories. The mean similarity of events increased with specificity, as expected. But differentiation of categories (within-category similarity compared to between-category similarity) was highest for super-ordinates, contrary to results with object categories. In Experiment 3, subjects were fastest in recognizing actions as belonging to events named at the basic level. In Experiment 4, subjects predominantly chose basic-level terms to name stories. We conclude that event taxonomies do show basic-level structure, albeit a less sharply defined and less stable structure than in object taxonomies. The benefits and hazards of extending models of object concepts to other entities, such as social events, are discussed.  相似文献   
975.
To provide evidence of the effects of academic training on causal attributions, university students in social science, commerce and engineering were compared at different points of their training in terms of their explanations of poverty and unemployment. Results of cross-sectional analyses showed no field differences in causal attributions at the beginning of the first academic year but significant differences at the end of the year, with social science students blaming the system more than commerce or engineering students. Longitudinal analysis showed that, within a six-month interval, the causal attributions of the students changed significantly as a function of their field of study. Differential employment prospects, while not accounting for the effects of academic training, were found to be related to attributional change. These results confirm the hypothesis that causal attributions are affected by socialization in a particular culture and that exposure to the culture of the social sciences reinforces a system-blame ideology. The implications of these findings for theories of the attribution process and theories of intergroup relations are discussed.  相似文献   
976.
Medical expertise asa function of task difficulty   总被引:4,自引:0,他引:4  
This paper is concerned with factors that disrupt the pattern of forward reasoning characteristic of experts with accurate performance. Two experiments are described. In the first, the performances of cardiologists, psychiatrists, and surgeons in diagnostic explanation of a clinical problem in cardiology were examined. In the second, the performances of cardiologists and endocrinologists in diagnostic explanation of clinical problems within and outside their domains of expertise were examined. The performances of researchers and practicing physicians are also compared. The results of Experiment 1 replicated earlier results regarding the relationship between forward reasoning and accurate diagnosis. There were no differences in recall as a function of expertise. Experts did not show any bias toward using specific knowledge from their own areas of expertise. The results of Experiment 2 showed that the breakdown of forward reasoning was related to the structure of the task. In particular, nonsalient cues induced some backward reasoning even in subjects with accurate diagnoses. Some differences were also found between the types of explanation used by researchers and practitioners. The practitioners referred more to clinical components in their explanations, whereas the researchers focused more on the biomedical components.  相似文献   
977.
This study explored a number of temporal (durational) parameters of consonant and vowel production in order to determine whether the speech production impairments of aphasics are the result of the same or different underlying mechanisms and in particular whether they implicate deficits that are primarily phonetic or phonological in nature. Detailed analyses of CT scan lesion data were also conducted to explore whether more specific neuroanatomical correlations could be made with speech production deficits. A series of acoustic analyses were conducted including voice-onset time, intrinsic and contrastive fricative duration, and intrinsic and contrastive vowel duration as produced by Broca's aphasics with anterior lesions (A patients), nonfluent aphasics with anterior and posterior lesions (AP patients), and fluent aphasics with posterior lesions (P patients). The constellation of impairments for the anterior aphasics including both the A and AP patients suggests that their disorder primarily reflects an inability to implement particular types of articulatory gestures or articulatory parameters rather than an inability to implement particular phonetic features. They display impairments in the implementation of laryngeal gestures for both consonant and vowel production. These patterns seem to relate to particular anatomical sites involving Broca's area, the anterior limb of the internal capsule, and the lowest motor cortex areas for larynx and tongue. The posterior patients also show evidence of subtle phonetic impairments suggesting that the neural instantiation of speech may require more extensive involvement, including the perisylvian area, than previously suggested.  相似文献   
978.
The short- and long-range apparent motion processes are discussed in terms of the statistical properties of images. It is argued that the short-range process, exemplified by the random-dot kinematogram, is primarily sensitive to the dipole statistics, whereas the long-range process, exemplified by illusory occlusion, is treated by the visual system primarily in terms of the tripole and higher statistical correlation functions. The studies incorporate the balanced dot, which is a unique stimulus element that permits high pass filtering while preserving detailed positional information. Low spatial frequencies are shown to be critical for texture segregation in random-dot kinematograms, independent of the grain size or number density of texture elements. Illusory path perception in the long-range process is shown not to require low spatial frequencies, but is sensitive rather to global temporal phase coherency. These results are interpreted in terms of the respective roles of the power and phase spectra in perceptual organization. The construction of balanced dots is discussed in detail.  相似文献   
979.
Sperling, Landy, Dosher, and Perkins (1989) argued that all previous research on the kinetic depth effect has been contaminated by stimulus artifacts, and they developed a new task that they believe can successfully overcome this problem. The present discussion offers a counter-argument that artifacts are not as pervasive in previous research as Sperling et al. imply and that their proposed method is subject to precisely the same limitations as earlier studies. Also discussed are some general guidelines of experimental design in this type of research to minimize the possibility that subjects will adopt an inappropriate response strategy that does not truly reflect their visual perceptions of three-dimensional form.  相似文献   
980.
Judgments of the color and shape of a stimulus specified by a cue indicating its location demonstrate stochastic independence. Evidence for the independence of color and orientation was obtained when the cue followed stimulus offset immediately, the cue followed stimulus offset by 2 s, and when either a central or peripheral precue focused attention on the cued stimulus at the time of its presentation. It appears that an object's color and orientation are represented independently even following the attentional focusing thought to support feature integration.  相似文献   
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