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901.
In the present investigation, we integrated self-theories (specifically, theories of cognitive consistency and self-esteem) with attribution theory. Our intent was to clarify the effects of different levels of self-esteem and performance satisfaction on causal internalization of academic performance. Subjects were 162 university students who attributed causality for their individual performances on a midterm examination. Attributions to four internal and four external causal sources were analyzed with a 2 × 2 (Self-Concept × Performance Satisfaction) MANOVA and with follow-up univariate F ratios. Most of the findings support the predictions based on self-esteem theory; i.e., satisfaction with performance, rather than consistency of performance with self-esteem, served as the primary influence on internalization of causality, with students internalizing satisfying outcomes more than dissatisfying outcomes. Cognitive-consistency theory and B. Weiner's (1979, Journal of Educational Psychology, 71, 3–25) attribution proposal regarding maintenance of a stable self-concept also received support, as attributions to the internal and stable causal sources of ability and general effort were a function of an interaction of self-esteem and performance satisfaction. Hence, neither self-theory adequately anticipated the effects of self-esteem and performance satisfaction on causal internalization. Rather, a consolidation of theories is needed to explain the results.  相似文献   
902.
903.
The present study examined the direction of the relation between sex role self-concept and depression. A total of 23 males and 32 females were given the Personal Attributes Questionnaire and the Beck Depression Inventory at two times separated by a 3-month interval. Results of a cross-lagged panel correlational analysis found no evidence for sex role orientation as a cause of depression. Instead, the data suggested that emotional well being precedes self-perceived instrumentality, but the influence of third variables could not be overlooked. The implications of these data are discussed with particular reference to the need for more complex theoretical formulations of the relation between self-perceived instrumentality and adjustment.  相似文献   
904.
We used a constrained classification task to examine the perceptual relations between global and local levels in hierarchical patterns composed of many, relatively small elements and those composed of few, relatively large elements. In Experiments 1 and 3 subjects were asked to make classifications based on "form" or "texture." In Experiments 2 and 4 they were asked to classify according to the "shape" of the configuration or the elements. The results indicate that configural and elemental levels are perceptually separable for many-element patterns when processed as form and texture: Subjects could attend to either level without being affected by variation along the irrelevant dimension. However, when the same many-element patterns were processed for global and local shape, subjects could not selectively attend to either level. For few-element patterns, global configuration and local elements appeared to be perceptually integral dimensions. These results are relevant to two issues: the global precedence hypothesis and the explanations of integral and separable dimensions.  相似文献   
905.
We describe a distributed model of information processing and memory and apply it to the representation of general and specific information. The model consists of a large number of simple processing elements which send excitatory and inhibitory signals to each other via modifiable connections. Information processing is thought of as the process whereby patterns of activation are formed over the units in the model through their excitatory and inhibitory interactions. The memory trace of a processing event is the change or increment to the strengths of the interconnections that results from the processing event. The traces of separate events are superimposed on each other in the values of the connection strengths that result from the entire set of traces stored in the memory. The model is applied to a number of findings related to the question of whether we store abstract representations or an enumeration of specific experiences in memory. The model simulates the results of a number of important experiments which have been taken as evidence for the enumeration of specific experiences. At the same time, it shows how the functional equivalent of abstract representations--prototypes, logogens, and even rules--can emerge from the superposition of traces of specific experiences, when the conditions are right for this to happen. In essence, the model captures the structure present in a set of input patterns; thus, it behaves as though it had learned prototypes or rules, to the extent that the structure of the environment it has learned about can be captured by describing it in terms of these abstractions.  相似文献   
906.
Recent efforts to build computer simulation models of mental imagery have suggested that imagery is not a unitary phenomenon. Rather, such efforts have led to a modular analysis of the image-generation process, with separate modules that can activate visual memories, inspect parts of imaged patterns, and arrange separate parts into a composite image. This idea was supported by the finding of functional dissociations between the kinds of imagery tasks that could be performed in the left and right cerebral hemispheres of two patients who had previously undergone surgical transection of their corpus callosa. The left hemisphere in both subjects could inspect imaged patterns and could generate single and multipart images. In contrast, although the right hemisphere could inspect imaged patterns and could generate images of overall shape, it had difficulty in generating multipart images. The results suggest a deficit in the module that arranges parts into a composite. The observed pattern of deficits and abilities implied that this module is not used in language, visual perception, or drawing. Furthermore, the results suggest that the basis for this deficit is not a difficulty in simply remembering visual details or engaging in sequential processing.  相似文献   
907.
In a three-choice discrimination task, pigeons learned to distinguish each letter of the alphabet from all the other letters and each of 16 random dot patterns from all the others. Discrimination errors were used to generate a matrix of interletter and interpattern similarities. Human estimates of letter similarity were obtained from the literature, and human subjects rated the similarity of the dot patterns. Pigeon and human performances were described and compared through correlation, multidimensional scaling, and cluster analysis. Fits of the data by simple-feature and template models were computed and compared. The correlation between pigeon and human similarity matrices was .68 for letters and .72 for dot patterns. The other analyses revealed broadly similar patterns of results from the two species but suggested also that, relative to human data, the best fits to the pigeon data required fewer dimensions, fewer features, and fuzzier templates. There was some indication that pigeon discriminations depended on relatively simple features, and several of these were tentatively identified. The different methods employed might have influenced these apparent differences between pigeons and humans, but, overall, the results suggest considerable cross-task and cross species generality in the processing of these simple forms.  相似文献   
908.
Six experiments with rats used a psychophysical choice procedure to study the internal clock used to discriminate duration. They investigated if the clock is sensitive to the signal value (associative strength) of a stimulus. The experiments involved two types of trials. On choice trials, a stimulus lasted a short (e.g., 3 s) or long (e.g., 12 s) duration; then the rats chose between two levers. The rewarded choice depended on the duration of the stimulus. On conditioning trials, the stimulus used on choice trials was presented, but it ended without food (extinction trials) or with food (pairing trials) regardless of what the rat did. The main stimulus minus accuracy with the long stimulus. Experiment 1 showed that extinction trials increased short bias relative to training without conditioning trials or to training with pairing trials. The rest of the experiments tested explanations of these results. The same results were found when extinction trials were the same duration as the short stimulus (Experiment 2), when extinction trials were a random duration (Experiment 5), and when the signal value of the conditioned stimulus was changed in another way (Experiment 6). The effect of conditioning trials was modality specific (Experiments 3 and 4). Of the explanations considered, the best one--the only one not contradicted at least once--is that changing the signal value of a stimulus changes how the clock times the stimulus. Reducing signal value reduces the measured duration.  相似文献   
909.
In laboratory rats (as in humans) a low-intensity tone that precedes a high-intensity burst of noise by approximately 100 ms can reduce the amplitude of the startle reaction elicited by the burst of noise. A series of four experiments with rats investigated the relation between the inhibitory effects of tonal frequency change and the length of the silent period (gap) preceding it. The major findings were the following: (a) A gap in an otherwise continuous pure tone inhibited startle when the gap occurred approximately 100 ms prior to the noise burst. (b) Although an increase in gap duration increased the inhibition afforded by the gap, the maximum inhibition was yielded by gaps of 100 ms and greater; this maximum was equivalent to the inhibition yielded by the presentation of a postgap tone alone. (c) A shift in tonal frequency across a 10-ms gap yielded more inhibition than did the same gap with no frequency shift; again the shift yielded equivalent inhibition to the presentation of the postgap tone alone. (d) An increase in the frequency shift increased inhibition when the shift occurred across a 10-ms gap, but not when the shift occurred across a 100-ms gap.  相似文献   
910.
Deep dyslexia in childhood?   总被引:1,自引:0,他引:1  
Deep dyslexia is an acquired reading disorder in which semantic substitutions (e.g., city read as town) are made in reading single isolated words. In this paper, evidence for deep dyslexic-type errors is presented from the word-recognition responses of six children, aged 7 years and 0 month to 8 years and 9 months, with severe reading disorders. These semantic substitutions occur in the absence of phonological skills. Therefore, it appears that there exists a small subset of developmental dyslexics who at the beginning of acquisition of reading skills are able to engage in semantic processing, but who show severe impairment of phonological processing. The existence of these reading errors indicate that the use of a phonological code is not necessary to extract meaning from the printed word.  相似文献   
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