The effects of anxiety and intelligence on concept formation

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Denny, John Peter, 1934-

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The goals of this study were to investigate the effects of anxiety and intelligence upon proficiency in concept formation, On the basis of an extension of Spence’s theory of anxiety and performance to incorporate intelligence as a variable, it was predicted that anxiety and intelligence would have interactive effects on proficiency in concept formation. This expectation was based on the assumptions that the effects of anxiety on proficiency would interact with those of task difficulty, and that task difficulty was a function of the intelligence of the subject as well as the intrinsic complexity of a task. Specifically, It was expected that if task complexity was held constant, higher levels of anxiety would facilitate concept formation for high Intelligence subjects and impair concept formation for low intelligence subjects. The subjects were 56 male students enrolled in introductory psychology who scored in the extreme quartiles on the Taylor Manifest Anxiety Scale. The high and low anxiety groups were each divided into high and low intelligence groups by splitting them at the median intelligence score for the total group. This procedure yielded four experimental groups designated HiA-HiIQ, LoA-’HiIQ, HiA-LoIQ, and LoA-LoIQ. All subjects were given two concept formation tasks, derived from those developed by Bruner, and required to deduce the attributes which constituted the concept from information provided as follows: the attributes included in the concept were deducible primarily by comparing negative instances of the concept to an initial positive instance, whereas the attributes not included in the concept were deducible by comparing positive instances to the initial positive instance. The necessary information was provided within the first nine instances; four additional redundant instances were given. After the subjects had examined each instance, they were required to report their conclusions about the concept by recording either 1) that they knew the attribute was included in the concept (I), or 2) that they knew the attribute was not included (N), or 3) that they did not know whether the attribute was or was not included (?). The subjects’ reports were scored correct or erroneous by comparing them to the report that could be correctly deduced from the information given by the instances presented. The results for correct r snorts of knowledge of attribute inclusion showed that, as predicted, anxiety facilitated the concept formation proficiency of high intelligence subjects, and interfered with the concept formation proficiency of low intelligence subjects. This finding was explicated by examining the subjects’ erroneous reports, erroneous reports were divided into six error types depending upon the report made by the subject as compared to the report that co Id be correctly deduced. Interactive effects of anxiety and intelligence were found only for those types of erroneous reports in which the information given established that an attribute either was (I) or was not (N) included in the concert but the subject made the wrong one of these two reports. The fact that this effect was found for only this kind of error was interpreted to be consistent with the extended theory of anxiety and performance. Additional findings showed that high intelligence subjects and low intelligence subjects tended to make different types of errors in concept formation. For the first task only, high intelligence subjects made more erroneous reports than did low intelligence subjects of the type in which they reported that they did not know about the inclusion of an attribute in the concept(?), when they could have deduced that it was included (I). Low intelligence subjects made many more errors than high intelligence subjects of the type in which they reported that an attribute was included in the concept (I), when the information had not established whether or not it was included (?).



This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy.



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