Date of Award
Doctor of Philosophy (PhD)
Lee R. Brooks
For many natural categories, there is idiosyncratic information contained in the perceptual stimuli that is not likely to be represented in an analytic description of those stimuli, and thus is likely to be ignored during attempts to establish an abstracted, probabilistic description of the category. This idiosyncratic perceptual information is useful, however, in the identification of distinct individuals within a category and, therefore, will be important in more nonanalytic, exemplar based classification procedures. The present work addresses two such sources of perceptual information: (1) Feature Individuation, the specific manner in which each separate feature is manifested in an individual item, and (2) Holistic Individuation, the manner in which the item's separate features cohere into an individuated gestalt whole. Data from Experiment Sets 1 and 2 indicate that the presence of either source of perceptual information will have an impact on classification behaviour. Furthermore, the extent of this impact is, at least in part, a function of whether subjects are provided with the classification rule prior to training or are expected to induce the classification rule through repeated feedback during training. Data from Experiment Set 3 indicate that if both sources of perceptual information are present, holistic individuation of the stimuli has priority. The presence of individuated features is not sufficient to produce exemplar based transfer if an item's holistic individuality is altered, but will affect responding if the holistic nature of the stimuli is eliminated during the transfer phase of the experiment. Finally, data from Experiment Set 4 indicate that learning about the two types of nonanalytic information does not appear to be incompatible with learning about the analytic information contained in the stimuli. Learning to use these various sources of information for the purposes of classification, however, are somewhat antagonistic.
Regehr, Glenn, "Perceptual manifestations of an analytic structure: The priority of holistic individuation" (1992). Open Access Dissertations and Theses. Paper 3838.