Psychology ETDs

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The experiment tested the acquired distinctiveness of cues (ADC) and acquired equivalence of cues (AEC) hypotheses. The ADC hypothesis predicts that learning distinctive responses to similar stimuli will decrease the amount of stimulus generalization (SG) between the stimuli. The AEC hypothesis predicts that learning the same response to two stimuli will increase the amount SG between the stimuli. The design used to test these hypotheses was a mixed list design; thus fifty Ss were run in a single group to which all the experimental conditions were administered. The experiment was conducted in h=three stages. In the first stage (pretraining) eight shapes were presented to all Ss using a standard PA procedure. The eight shapes consisted of four sets of shapes, each set consisting of a prototype shape and a variation constructed from that shape. A different experimental treatment was applied to each set of shapes. For one set S learned a common CVC label to both members of the set (E condition); for a second set S learned a different CVC label for each member of the set (D condition); for a third set S only observed each stimulus in the set as it was presented but was not required to learn a label for either stimuli (00 condition); and for a fourth set S learned a CVC label for the prototype but only observed the variation (OD condition). A fifth set of shapes which did not appear in pretraining but was used in subsequent stages of the experiment served as a no pretraining control. In stage II, S learned to label with a noun the prototype shape from each of the five sets representing the five pretraining conditions (E, D, OO, OD, and control). The purpose of stage II was to establish a new instrumental response to one of the members of each stimulus set. The amount of SG of this response within a set of stimuli as function of pretraining conditions was measured during the third stage. In the third stage (SG test), S saw each of the five prototypes and a family of variations of each prototype, including the variation used in pretraining. The S was asked to identify the shapes used in stage II by giving the name, learned in stage II, of the stimulus when S thought that one of those stimuli appeared. The results supported the AEC hypothesis- - there was more SG between the stimuli given E pretraining than between the stimuli given OO or no pretraining. The results further indicated that the effects of E pretraining are not specific to the stimuli used in pretraining but generalized to stimuli similar to those used in pretraining. In contrast to the support for the AEC hypothesis, no support was found for the ADC hypothesis. The lack of support for the ADC hypothesis may be attributed to the fact that the distinctive responses used in D pretraining were not overlearned to the extent that the E responses were overlearned during E pretraining. Thus, because of possible unlearning during stage II, the distinctive responses may not have been available to the Ss during the SG test to mediate decreased SG.

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First Committee Member (Chair)

Henry Carleton Ellis

Second Committee Member

Frank Anderson Logan

Third Committee Member

David Wilmot Bessemer



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