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901.
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   
902.
903.
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   
904.
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   
905.
This article introduces a new technique designed to study the flow of information through processing stages in choice reaction time tasks. The technique was designed to determine whether response preparation can begin before stimulus identification is complete ("continuous" models), or if a stimulus must be fully identified prior to any response activation ("discrete" models). To control the information available at various times during stimulus identification, some relevant stimulus characteristics were made easy to discriminate and some were made hard to discriminate. The experimental strategy was to look for effects of partial output based on information conveyed by characteristics that were easy to discriminate. The technique capitalized on the fact, demonstrated in Experiment 1, that preparation of two response fingers on the same hand is more effective than preparation of two response fingers on different hands. The usefulness of partial output was varied by manipulating the assignments of stimuli to responses. For some mappings partial information could contribute to effective response preparation because the responses consistent with partial information were assigned to fingers on the same hand. For other mappings partial information could not contribute to effective response preparation because the responses consistent with partial information were assigned to fingers of different hands. Performance differences between these mappings were considered evidence that partial information about a stimulus was transmitted to response activation processes before the stimulus was uniquely identified, and thus were considered evidence against discrete transmission of information about the stimulus as a whole. A variety of stimulus sets were studied; the results suggest that information is transmitted discretely with respect to stimulus codes, although distinct codes activated by a single stimulus may be transmitted at different times.  相似文献   
906.
907.
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   
908.
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   
909.
What career decision-making procedures enable people to make decisions that yield consequences congruent with their own values? The 40 “best” (most congruent) and 40 “worst” decision makers on the Career Decision Simulation were compared in a sample of 148 community college students. No significant differences appeared in the amount of double checking, number of occupations and information sources checked, amount of information collected, decision time required, and the proportion of information sought about high values. The “best” decision makers, however, were significantly more persistent in immediately seeking more information about an occupation that seemed to match one of their most important personal work values. Following a values-guided search appears more effective than simply searching exhaustively.  相似文献   
910.
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