Cerebral Blood Flow, Metabolism and Cognitive Function in Normal Aging and Dementing Disorders

Cerebral Blood Flow, Metabolism and Cognitive Function in Normal Aging and Dementing Disorders

Georg Deutsch, Ph.D.
University of Alabama at Birmingham, USA

Course Prerequisites:

Basic neuropsychology or behavioral neurology, including an appreciation for the historical development of our understanding of brain-bevahior relationships. Some familiarity with neuroimaging methods, including PET and MRI, and the kinds of issues they can and cannot address. Some previous exposure to the cognitive changes associated with normal and abnormal aging. An appreciation for current debate surrounding "mild cognitive impairment" and its relationship to dementia.

Course Description:

This course will cover the technical aspects and a number of clinical and research applications of today's most powerful neuroimaging techniques, with an emphasis on normal and abnormal aging. The techniques will include cerebral blood flow measurements with SPECT, PET and MRI techniques, metabolic imaging with PET, and neuronal activity measurements with magnetoencephalography (MEG). Each imaging modality will be examined in terms of what is precisely being measured, its spatial and temporal characteristics, extent to which true quantification is achieved, relative strengths and weaknesses, and appropriateness of application to specific clinical and research issues. The course will emphasize neuroimaging studies of cognitive function, including the methods employed in current attempts at “mapping” brain function and building relationships between neuropsychological findings and neuroimaging. Issues of analysis will be addressed, including the distinction between hypothesis driven and data driven applications, the use of regions-of-interest (ROI) analysis and statistical parametric mapping (SPM). The issue and appropriateness of pattern analysis versus true absolute quantification will be discussed, with examples presented showing how truly quantitative imaging techniques can lead to very different interpretations of data acquired by techniques in which “activation” is defined simply as the redistribution of brain activity.

The effects of normal aging on baseline cerebral activity and the “activation” associated with sensory-motor and cognitive function will be examined. These effects will be compared to other major factors contributing to group differences in cerebral blood flow and metabolism, such as gender. Some of the complex and controversial issues of relating performance to brain activity will be addressed, as well as the respective roles of novelty, practice and habituation. The course will then turn to some of the major diseases affecting cerebral blood flow, metabolism, and cognition, including Alzheimer's disease, microvascular disease of grey and white matter, and stroke. The typical changes observed in each disease category in both resting and activated state measures of brain activity will be discussed, as well as the possible relationships with specific patterns of cognitive dysfunction. The process of compensation and recovery to cerebral injury will be covered in terms of how it is both a potential confound to understanding brain function and an obviously vitally important mechanism. This will include an emphasis on how recovery and compensation may differ in cases of primary degenerative disease (e.g., Alzheimer’s) and cerebrovascular disease. Finally, we will spend some time discussing the possible trade offs in terms of positive and negative effects of aging on human intellectual ability and other skills.

Reading List

Selected journal articles and other reading material will be distributed at the lectures.