Psychology ETDs

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Three experiments investigated the coding strategies formed with Constant and variable input of letter and digit series. Recent research in memory indicates that varied presentations of perceptually-grouped letter sequences will lead to superior recall relative to conditions in which the same sequences are presented in a fixed or constant manner. The perceptual regrouping hypothesis advanced by Ellis et al. implicates stimulus structure as a principal factor contributing to the superiority in recall of variable stimulus training. The present experiments were designed as a test of this assumption, Ss were trained with stimuli varying in structure (meaningfulness and/or pronounceability) and presented as either a constant or variable group structure. A second experiment examined recall superiority due to variable stimulus training with manipulations in the features of the test task. A third experiment examined the recall of structured and unstructured digit series presented as either a constant or variable grouping. There were three principal findings of the experiments. First, in each experiment, the major assumption of the perceptual regrouping hypothesis was supported. Specifically, varied stimulus training led to superior recall of structured letter and digit sequences. Second, the results indicated that structure with letter sequences may be defined in terms of the meaningfulness and pronounceability of the sequences and that each attribute contributed differently to the encoding process. Finally, the probability of adopting the strategy of regrouping the stimuli was found to depend upon both the meaningfulness of the stimuli as well as the manner by which Ss were tested.

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First Committee Member (Chair)

Henry Carleton Ellis

Second Committee Member

John Paul Gluck Jr.

Third Committee Member

G. Robert Grice



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Psychology Commons