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The overall objective of this dissertation was to increase scientific understanding of brain reserve. Chapter 1 describes how brain reserve has come to be viewed in two distinct ways: differential expression of brain injury on the basis of individual differences in gross brain properties (neurological), or on the basis of lifespan patterns of complex mental activity (behavioural). Evidence in the Alzheimer???s disease and ageing literature has been extensive, yet with conflicting reports. In order to better evaluate this evidence, a systematic review of cohort studies is the focus of Chapter 2. Complex mental activity was found to be associated with reduced incidence of dementia and slowed rate of cognitive decline. Neurological brain reserve evidence was limited. A major task of this dissertation was to develop a more standard and complete behavioural brain reserve instrument. Chapter 3 relates the development of the Lifetime of Experiences Questionnaire (LEQ) in a group of 86 healthy elderly. The LEQ had adequate levels of internal consistency and reliability. In a validation test, higher LEQ scores were also found to predict attenuated cognitive decline over 18 months independent of covariates including premorbid IQ. Chapter 4 describes how both LEQ (as a measure of behavioural brain reserve) and intracranial volume (as a measure of neurological brain reserve) significantly predicted cognitive decline over three years in a sample of 70 aged subjects. Total LEQ was furthermore significantly correlated with hippocampal volume independent of intracranial volume, and this association mediated the relationship with cognitive decline. Behavioural brain reserve may therefore work by protecting individuals from hippocampal atrophy. The fifth chapter explores therapeutic and neurobiological aspects of behavioural brain reserve in a preliminary fashion. A randomized-control mental activity trial was run with 20 healthy elderly who received repeat magnetic resonance spectroscopy. Mental activity subjects were found to have selective and sustained upregulation of phosphocreatine metabolism in the hippocampal region, a finding of potential neuroprotective significance. Experience-dependent neuroplasticity is proposed as a unifying framework in the final chapter, allowing synthesis of the present findings and reconciliation of the neurological and behavioural approaches to brain reserve.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed on Mar. 13, 2007). PDF text: xv, 250 p. : ill. UMI publication number: AAT 3222555. Includes bibliographical references. Also available in microfilm, microfiche and paper format.

Thesis (Ph. D.)--York University, 2000. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 112-127). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ59153.

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 149-163). Also available in print.

Thesis (Ph. D.)--York University, 1999. Graduate Programme in Philosophy. / Typescript. Includes bibliographical references (leaves 81-87). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ43457.

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Background: Great strides have been made in childhood cancer treatment efficacy over the past two decades leading to improved survival rates, and now attention is being directed toward identifying and understanding complications that affect many of these patients as they reach adulthood. Obesity is a well‐recognized late effect that has many potential long‐term consequences some of which include cardiovascular disease, type II diabetes mellitus, dyslipidemia and even death. Materials/Methods: We conducted a retrospective chart review to determine the prevalence of obesity among survivors of pediatric brain tumors 5 years after the completion of therapy and compare this to the general pediatric population of the same age. We also sought to identify potential risk factors for the development of obesity among survivors of childhood brain tumors. Obesity was defined as a body mass index (BMI) greater than the 95th percentile for age and gender as defined by the most recent Center for Disease Control growth curves. Results: We identified 96 patients who met our inclusion criteria, however only 43 had follow‐up data at 5 years after the completion of therapy to be included in final analysis. Of 43 patients, 5 (11.63%) were obese 5 years after completion of therapy. The CDC sites general population obesity rates in three age groups: 2‐5 years (8.4% obesity rate), 6‐ 11 years (18% obesity rate), 12‐19 years (21% obesity rate). Using CDC guidelines, we found no significant difference between the obesity rate among the brain tumor survivor population for each age group and the general population, p‐values of 0.865, 0.865, and 0.249 respectively. Conclusion: Our small sample size was likely not adequate to find a significant difference between the two groups or identify risk factors associated with the development of obesity. Larger studies are needed to further examine the risk of obesity among pediatric brain tumor survivors and to identify risk factors associated with this late effect.