Psychology ETDs

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The role of attentional and stimulus encoding factors in animal memory processes has recently received increased discussion. Central to the assumed processes of selective attention and stimulus encoding is the role of selective training or practice. The present experiment addressed the possibility of attentional or encoding factors in the appearance of differential retention effects between stimulus dimensions and the reversal of these effects by selective training. Four pigeons were trained to perform a 3-second delayed matching-to-sample task in which some trials began with a compound sample stimulus, i.e., a geometric form superimposed on a color. When the choice stimuli appeared, only one of the two stimulus dimensions was represented. During the first 18 probe sessions in which compound sample stimuli appeared, both color and form were relevant for correct matching on an equal proportion of the compound sample trials. Next, subjects were given 6 sessions in which the choice stimuli in the compound sample trials were only form-correct. Subjects were then given three additional sessions in which either color or form was relevant on a given compound trial. Results indicated that subjects performed at lower accuracy levels on trials beginning with compound samples than on trials beginning with single sample stimuli. Furthermore, compound trials in which color was relevant were less impaired than compound trials in which form was relevant. Limited experience with only form-correct compounds did little to change the direction of color-form differences. The utilization of selective training procedures in delayed matching-to-sample tasks as well as the implications of attentional and encoding factors for classical theories of memory processes were discussed.

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First Committee Member (Chair)

Douglas Peter Ferraro

Second Committee Member

John Paul Gluck Jr.

Third Committee Member

G. Robert Grice



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Psychology Commons