No description available.

The main aim of the thesis was to investigate the nature of the cognitive mechanisms which underlie performance on specific visuo-spatial working memory tasks, with the emphasis on exploring the extent of central executive involvement. This research began with an attempt to investigate performance on two standard visual and spatial tasks in a small sample of mild-to-moderate AD patients, and compare this with performance on two adapted versions of the tasks (Experiments 1 & 2). The tasks were adapted to increase the ecological validity, but this adaptation appeared to alter the demands of the tasks, which prevented their further investigation as useful alternatives. The following experiments concentrated on investigating visual and spatial working memory in healthy populations. Experiments 3, 4, 5 and 6 employed a dual-task paradigm, whereby specific visual and spatial working memory tasks were combined with tasks assumed to involve executive processes. Experiments 3, 4 and 5 employed oral random digit generation as an executive task. The results of Experiments 3 and 5 indicated that visuo-spatial tasks which involve sequential processing show more interference with random digit generation than visuo-spatial tasks which involve simultaneous processing. The findings of Experiment 4 suggested that, when both item and order information are presented (i.e. with sequential presentation), subsequent recall or visuo-spatial material is attention demanding regardless of whether item only, order only, or both item and order information are required in response. These findings appear to indicate that visuo-spatial tasks which involve sequential processing require executive resources to a greater extent than visuo-spatial tasks which involve simultaneous processing. However, oral random generation is a sequential task, and requires the maintenance of serial order (in order to produce a random sequence). Therefore an alternative interpretation could be that the sequential nature of the oral random generation task gave rise to the pattern of selective impairment on sequential visuo-spatial tasks, rather than more general executive load.

Thesis (B.A.)--Haverford College, Dept. of Psychology, 2008. / Includes bibliographical references.

Thesis (B.A.)--Haverford College, Dept. of Psychology, 2008. / Includes bibliographical references.

Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Education." Includes bibliographical references (p. 83-88).

No description available.

This thesis provides a conceptual and empirical analysis of implicit concept formation. A review of concept formation studies highlights the need for improving existing methodology in establish- ing the claim for implicit concept formation. Eight experiments are reported that address this aim. A review of theoretical issues highlights the need for computational modelling to elucidate the nature of implicit learning. Two chapters address the feasibility of different exemplar and Connectionist models in accounting for how subjects perform on tasks typically employed in the implicit learn- ing literature. The first five experiments use a concept formation task that involves classifying "computer people" as belonging to a particular town or income category. A number of manipulations are made of the underlying rule to be learned and of the cover task given subjects. In all cases, the knowledge underlying classification performance can be elicited both by free recall and by forced choice tasks. The final three experiments employ Reber's (e.g., 1989) grammar learning paradigm. More rigorous methods for eliciting the knowledge underlying classification performance are employed than have been used previously by Reber. The knowledge underlying clas- sification performance is not elicited by free recall, but is elicited by a forced-choice measure. The robustness of the learning in this paradigm is investigated by using a secondary task methodol- ogy. Concurrent random number generation interferes with all knowledge measures. A number of parameter-free Connectionist and exemplar models of artificial grammar learning are tested against the experimental data. The importance of different assumptions regarding the coding of features and the learning rule used is investigated by determin- ing the performance of the model with and without each assumption. Only one class of Connectionist model passes all the tests. Fur- ther, this class of model can simulate subject performance in a different task domain. The relevance of these empirical and theoretical results for understanding implicit learning is discussed, and suggestions are made for future research.

Thesis (M.A.)--Cleveland State University, 2008. / Abstract. Title from PDF t.p. (viewed on July 7, 2008). Includes bibliographical references (p. 31-36). Available online via the OhioLINK ETD Center. Also available in print.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 59-64).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 214-234). Available also in a digital version from Dissertation Abstracts.