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951.
The acquisition of observing.   总被引:6,自引:6,他引:0       下载免费PDF全文
Pigeons were exposed to stimuli correlated with the presence or absence of a variable-interval 60-second schedule of reinforcement only while they depressed a crossbar or "perch." In the first experiment, the stimuli were different tilts of a line displayed on the key. When the difference in brightness between the line and the background (salience) was maximal, seven of eight birds acquired the discrimination, but when the difference was reduced by 50%, only one succeeded. In the second experiment, wavelength of chamber illumination served as the relevant dimension. Neither experiment showed a large effect attributable to the magnitude of the difference (disparity) between the positive and the negative stimulus. Individual differences in time spent observing were positively correlated with level of discrimination in the presence of the stimuli. All birds produced the positive stimulus for a greater proportion of the available time than they did the negative stimulus. This may be the mechanism that provides selective reinforcement of observing. Finally, the formation of a discrimination was analyzed in terms of changes in the proportion of time spent in contact with the discriminative stimuli.  相似文献   
952.
953.
Just and Carpenter (1980) presented a theory of reading based on eye fixations wherein their “psycholinguistic” variables accounted for 72% of the variance in word gaze durations. This comment raises some statistical and theoretical problems with their use of simultaneous regression analysis of gaze duration measures and with the resulting theory of reading. A major problem was the confounding of perceptual with psycholinguistic factors. New eye fixation data are presented to support these criticisms. Analysis of fixations within words revealed that most gaze duration variance was contributed by number of fixations rather than by fixation duration.  相似文献   
954.
How do we use place information in a number comparison task involving multidigit numbers? In four experiments, subjects identified stimulus numbers as larger or smaller than the number 5,000 in a choice reaction time task. As the difference between the number of places in the stimulus number and the number of places in the standard decreased, response time and errors significantly increased. When the number of places was held constant, the type of numeric information extracted depended on the value of the standard (5,000 or 5,555). In some cases, irrelevant place information affected choice time.  相似文献   
955.
956.
This study investigated recognition memory of self-photographs which had been previously rated by subjects for their degree of reference to an imaginal prototype of “real self.” The number of false alarms to NEW photographs was found to increase with degree of self-reference to the imaginal prototype with the exception of photographs rated highest in self-reference. Females were reliably superior to males in self-recognition. Males and females also differed in nonverbal behaviors reflecting differences in their image of real self. Results were interpreted as supporting an hypothesis that the self functions as a cognitive prototype which has both imaginal and verbal characteristics.  相似文献   
957.
Deep agraphia     
A case of agraphia is documented which resembles in every respect the pattern of results obtained in deep dyslexia. Pronounceable pseudowords could not be written to dictation while concrete nouns were more accurately transcribed than abstract nouns. Verbs and functions words were written very poorly and oral spelling was impaired. In addition, semantic paragraphias were present. In contrast to the deficit observed in writing, no such impairment was found for reading. It is concluded that writing can occur without phoneme-grapheme conversion and that codes generated for reading are functionally distinct from codes generated for writing.  相似文献   
958.
The fractionation of arithmetical skills: A single case study   总被引:14,自引:0,他引:14  
A single case study of a patient with a selective impairment of arithmetical calculation is reported. DRC became severely acalculic after sustaining a left parietal intra-cerebral haematoma. His numeracy skills were documented as fully as possible. It was found that his knowledge of the significance of individual numbers and his concept of quantity appeared to be intact, but simple addition, subtraction and multiplication were all performed laboriously and inaccurately and his performance was inconsistent from trial to trial. Further it was shown that it was his knowledge of arithmetical facts not his knowledge of arithmetical operations which was impaired. The findings are discussed in relation to models of arithmetical calculation and it is concluded that for DRC there was a deficit in accessing one category of verbal semantic knowledge systems, namely arithmetical facts.  相似文献   
959.
Based on an attributional analysis of menstrual distress, the present study examined how a woman is evaluated when she attributes an instance of negative social behavior to the approach or onset of menstruation. College men and women were asked to imagine an interaction in which a woman behaves very irritably and then gives one of several excuses for her negative behavior, two of which were menstrual related. Subjects evaluated each excuse in terms of (1) degree of annoyance, (2) blameworthiness, and (3) internality versus externality. The results showed consistent relationships between these evaluations and both sex of subject and general attitudes about menstruation. Males tended to see menstrual-related excuses as less blameworthy and more external than did females. In addition, general attitudes regarding the debilitating effects of menstruation predicted greater tolerance toward the use of menstrual excuses. These results are discussed in terms of their implications for the socialization and continuing reinforcement of menstrual distress.The research reported in this article was supported by grants SOC-7602137 and SOC-7602179 from the National Science Foundation. The authors wish to thank Russ Fazio for his help in collecting the data and Al Rogers and Terry Balaban for their help in analyzing the data. Diane N. Ruble is now at New York University. Ann K. Boggiano is now at the University of Colorado.  相似文献   
960.
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