This study examined the relationship between neuropsychological constructs of sensory-motor functioning and cognitive ability constructs in the Cattell-Horn-Carroll (CHC) (Carroll, 1993) theory. Two studies were conducted For the first study, the Dean-Woodcock Sensory Motor Battery (SMB) (Dean & Woodcock, 1999) was administered to 800 individuals. A factor analysis and a confirmatory factor analysis were used to investigate and develop a factor structure of the SMB. Results from this study suggest sensory and motor tests significantly share common variance and a hierarchical, multifactorial model that included a higher-order factor of both sensory and motor tests best fit the data. The second study examined the SMB model, developed in the first study, in relation to the CHC (Cattell-Horn-Carroll) model of cognitive abilities, as measured by the Woodcock-Johnson Revised Tests of Cognitive Abilities (WJ-R) (McGrew, Werder, & Woodcock, 1991). For this study, the SMB and the WJ-R was administered to 411 individuals. A confirmatory model was tested that included the higher-order factor of the SMB as a broad ability within the CHC model. Results from this analysis suggest the higher order factor of the SMB does have a significant relationship with overall measures of cognitive ability of a similar level to other broad abilities in the CHC model, and significantly improves the fit of CHC model. These results support Roberts, Pallier, and Goffs (1999) argument for the inclusion of an additional broad ability in the CHC taxonomy that represents sensory and motor functioning. Additionally, this study provides empirical support for the utility of including neuropsychological tests of sensory and motor functioning in a comprehensive assessment of cognitive abilities (Dean & Woodcock, 1999). The implications for neuropsychological and psychometric assessment are discussed. / Department of Educational Psychology

The processing of information within the visual system is limited by several cognitive and neural bottlenecks. One critical bottleneck occurs in visual working memory (VWM), as the amount of information that can be maintained on-line is limited to three to four items. While numerous theories have addressed this limited capacity of VWM, it is unclear how processing bottlenecks in the initial selection and perception of visual information affect the number or precision of representations that can be maintained in VWM. The purpose of this dissertation was to examine whether early competition for resources within the visual system limits the number or precision of representation that can be maintained in VWM. To establish whether competitive interactions affect VWM, Chapters 1 – 4 tested whether performance on VWM tasks was related to the distance between memory items. The results of these experiments reveal that when objects are presented close together in space, VWM performance is impaired relative to when those same objects are presented further apart. Using a three-component model of continuous responses in a recall task, Chapters 3 – 4 demonstrated that the distance between objects primarily affects the precision of responses, and increases the number of non-target errors. Chapter 5 extended these findings to distractors, demonstrating that multiple distractors affect the precision and accuracy of VWM responses. Chapters 6 – 7 tested how attentional selection can bias memory representations, revealing that objects that are given high attentional priority were reported with greater precision. Finally, Chapters 8 and 9 examined bias-signals as a potential source of individual differences in VWM performance, revealing that high-performers have more precise representations of sub-capacity representations than low-performers. Together, these results reveal that VWM performance is limited by competition for representation within the visual system, and that attention plays a critical role in resolving competition and consequently, determining the contents of VWM.

This thesis is concerned with the computational modelling and simulation of physiological structures and cognitive functions of brains through the use of artificial neural nets. While the structures of these models are loosely related to neurons and physiological structures observed in brains, the extent to which we can accept claims about how neurons and brains really function based on such models depends largely on judgments about the fitness of (virtual) computer experiments as empirical evidence. The thesis examines the computational foundations of neural models, neural nets, and some computational models of higher cognitive functions in terms of their ability to provide empirical support for theories within the framework of Parallel Distributed Processing (PDP). Models of higher cognitive functions in this framework are often presented in forms that hybridise top-down (e.g. employing terminology from Psychology or Linguistics) and bottom-up (neurons and neural circuits) approaches to cognition. In this thesis I argue that the use of terminology from either approach can blind us to the highly theory-laden nature of the models, and that this tends to produce overly optimistic evaluations of the empirical value of computer experiments on these models. I argue, further, that some classes of computational models and simulations based on methodologies that hybridise top-down and bottom-up approaches are ill-designed. Consequently, many of the theoretical claims based on these models cannot be supported by experiments with such models. As a result, I question the effectiveness of computer experiments with artificial neural nets as an empirical technique for cognitive modelling.

This thesis represents a work of basic research into dimensions of time and space, referred to as temporality, in the condition Alzheimer's dementia. In this theoretical, text-based study, temporality was explored as a dual exposition, in ordinary functioning and in impaired functioning. As expected, the influence of time and space, was found to enter each experience and was observable in every facet of human endeavour and behaviour. Significantly, however, fundamental new interpretations were developed regarding the role of temporality in human life and functioning. Temporality was identified as an essential, common component of both cognitive functions and cohesive identity construction in a unified view of body and mind. As an illustration and clarification of this concept of temporality as a subjective, psychological clock, an innovative framework, the Personal Space-Time model was developed.

Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: Suzanna Becker. Includes bibliographical references.

Thesis (M.A.)--York University, 2006. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 70-73). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://proquest.umi.com/pqdweb?index=0&did=1240699451&SrchMode=1&sid=15&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1195058296&clientId=5220

Thesis (Ph. D.)--University of Sydney, 2002. / Title from title screen (viewed Apr. 28, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Psychological Medicine, Faculty of Medicine. Includes bibliography. Also available in print form.

Thesis (M.A.)--Carleton University, 2008. / Includes bibliographical references (p. 79-90). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 93-103).

Thesis (Ph. D.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 152-163). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.