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241.
Social phobia and avoidant personality disorder (APD) may be given as comorbid diagnoses. However, it is not known if the labels provide independent, useful diagnostic information. We classified social phobics by social phobia subtype and presence of APD. Generalized social phobics with and without APD (ns = 10 and 10) and nongeneralized social phobics without APD (n = 10) were distinguished on measures of phobic severity. The generalized groups also showed earlier age at onset and higher scores on measures of depression, fear of negative evaluation, and social anxiety and avoidance than did the nongeneralized group. APD criteria of general timidity and risk aversion were more frequently endorsed by social phobics with APD. The data suggest that both the generalized subtype of social phobia and the presence of APD do provide useful diagnostic information but the additional diagnosis of APD may simply identify a severe subgroup of social phobics.  相似文献   
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The multiple and long-term effects of functional communication training relative to a common reductive procedure (time-out from positive reinforcement) were evaluated. Twelve children participated in a functional analysis of their challenging behaviors (Study 1), which implicated adult attention as a maintaining variable. The children were then matched for chronological age, mental age, and language age and assigned to two groups. One group received functional communication training as an intervention for their challenging behavior, and the second group received time-out as a contrast. Both interventions were initially successful (Study 2), but durable results were achieved only with the group that received functional communication training across different stimulus conditions (Study 3). Students whose challenging behaviors were previously reduced with time-out resumed these behaviors in the presence of naive teachers unaware of the children's intervention history. The value of teaching communicative responses to promote maintenance is discussed as it relates to the concept of functional equivalence.  相似文献   
245.
Subjects presented with sets of three samples, two of distilled water and one of tap water, were significantly more consistent in choosing the tap water as preferable than they were in identifying it as the odd sample in the set. The result is opposite to the prediction of high-threshold models of sensory discrimination, which say that if a difference is not noticed, preferences will be random, whereas if a difference is noticed, preferences may still be in either direction. The result can be quantitatively explained by a model advanced by Frijters to explain an analogous anomaly found with the triangle test used in the food industry. Applying his model to the observed proportions yields essentially equivalent estimates of sensory difference (d' = 1.5, approximately) from the two tasks, and a direction of preference almost unanimously in favor of the tap water that was used. Since the model predicts that the proportion of subjects choosing the odd item will depart further from chance in the preference task than in the oddity task, the former has greater power to reject the null hypothesis of no sensory difference if one exists and if preference is overwhelmingly in one direction.  相似文献   
246.
The scale illusion (Deutsch, 1975) shows the importance of frequency range in the perceptual organization of a sequence of notes. This paper includes three experiments on the scale illusion. Experiments 1 and 2 demonstrated that if the structure of the pattern of notes used in the original scale illusion study is altered slightly, by adding or subtracting a pair of notes from the ends of the sequence, there is a significant decrease in the rate of frequency-based responses, suggesting a weaker illusion. Experiment 3 investigated two features of the note patterns that may have led to this change. Specifically, it asked whether the decrease in the strength of the illusion is due to (1) the nature of the notes at the extremes of the frequency range and/or (2) the nature of the notes at the crossing point of the two scales. While both sources were found to affect the strength of the scale illusion, the former had a greater influence.  相似文献   
247.
The Brain-Age Quotient (BAQ) of Reitan has been proposed as a means of studying age-related cognitive differences. This study examined age and education correlates of the BAQ and a BAQ short form. A heterogeneous group of 100 subjects were selected from the neuropsychological testing case records published by Golden, Osmon, Moses, and Berg in 1981, Boll (undated), and Reitan (undated). Results suggest the BAQ and the BAQ short form are not significantly correlated with age and education.  相似文献   
248.
Psychophysical studies with infants or with patients often are unable to use pilot data, training, or large numbers of trials. To evaluate threshold estimates under these conditions, computer simulations of experiments with small numbers of trials were performed by using psychometric functions based on a model of two types of noise: stimulus-related noise (affecting slope) and extraneous noise (affecting upper asymptote). Threshold estimates were biased and imprecise when extraneous noise was high, as were the estimates of extraneous noise. Strategies were developed for rejecting data sets as too noisy for unbiased and precise threshold estimation; these strategies were most successful when extraneous noise was low for most of the data sets. An analysis of 1,026 data sets from visual function tests of infants and toddlers showed that extraneous noise is often considerable, that experimental paradigms can be developed that minimize extraneous noise, and that data analysis that does not consider the effects of extraneous noise may underestimate test-retest reliability and overestimate interocular differences.  相似文献   
249.
The research was intended to identify the dimensions underlying self-perceived information needs and concerns of an elderly population. The spontaneously mentioned needs and concerns expressed in 271 letters from a sample of the population were extracted and a multidimensional scaling procedure was used to represent the 58 most frequently mentioned items in configurations of varying dimensionality. To interpret the multidimensional spaces, another sample of 176 elderly subjects was asked to rate the 58 concerns on eight properties. These ratings were then regressed onto the multidimensional configurations. The results indicate that the most frequently mentioned information needs and concerns of elderly persons can be parsimoniously understood in terms of three underlying dimensions: (1) Improving the Quality of Life vs Securing the Necessities of Life, (2) Health-related vs Not Health-related, and (3) Individual vs Societal Responsibility.  相似文献   
250.
A paradigm for studying oral sensory tactile function through use of single frequency vibration applied to the dorsal surface of the tongue was administered to a group of 10 young black women and 10 young white normal-speaking women. Analyses showed no differences between groups with regard to lingual vibrotactile threshold of sensitivity or suprathreshold magnitude-estimation scaling responses.  相似文献   
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