No description available.

University of Macau / Faculty of Arts and Humanities. / Department of English

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph. D.)--University of Oregon, 2000. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 199-211). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p9998034.

The focus of this paper is to apply some of the new analytic techniques to positron emission tomography (PET) data in order to test the neuroanatomical plausibility of two very specific models of language processing: the model of Geschwind (1965), and that of Petersen et al. (1988; 1989). Model plausibility was assessed by fitting both models to a word repetition and a synonym generation rCBF PET dataset using methods based on the examination of interregional correlations, and structural equation modeling. / Physiologically-based regions of interest were defined a priori through a review of PET activation literature. The current study demonstrated (1) the feasibility of using a priori defined physiological regions of interest in model evaluation, (2) the advantages of using structural equation modeling over interregional correlations, and (3) that neither model proved to be a particularly good fit to the data.

In the current work, the distinction between priming for associatively-related (AR) and unassociated semantically-related (SR) words is examined. Specifically, whereas associatively-related words demonstrate strong and robust priming effects when presented within the context of lexical-level tasks, generation of significant SR priming appears to require execution of an explicitly semantic task. This apparent levels-of-processing effect, if reflected in the neural-level implementation, would suggest that the mechanisms underlying priming may be localized to spatially and functionally distinct cerebral regions. In the first part of the thesis, an artifactual decision task (ADT) is developed and refined, which proved capable of producing strong immediate SR priming for auditorily presented words. Insertion of unrelated items between prime and target produced differential effects on priming, with AR targets exhibiting an interference effect that slowly diminished as more unrelated items were inserted. The nature of the underlying difference at the neural substrate level was subsequently examined in a PET imaging study, in which subjects performed an auditory ADT using both AR and SR words. Analysis of the cerebral blood flow patterns (CBF) using both simple contrasts, as well as partial least squares (PLS) analysis, found priming-related rCBF decreases in the left frontal regions, primarily within the inferior prefrontal cortex, and left-sided priming-related increases, localized primarily to the superior temporal gyrus, and the ventral temporal surface. Priming-related modulations were reflected by SR words, but not AR words. A behavioral PLS analysis demonstrated that an increase in both SR priming and AR interference effects was associated with increased activity with the extrastriate cortical regions, particularly on the left, suggesting a contribution of visual areas to both facilitatory and interference effects. The imaging findings are

No description available.

Thesis (Ph.D.)--University of Oklahoma, 1986. / Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.