Our primary goal is understanding the cognitive processes underlying episodic memory, processes that associate (bind) features of events into complex memories (encoding), consolidate them over time, and revive and evaluate them later. Among the consequences of normal aging, one of the most distressing is the sense of losing access to specific details of episodic memories. Consider not being able to remember whether you already paid a bill or called in your prescription renewal or only thought about doing so. These problems are more common than more severe deficits, such as Alzheimer's Dementia; an even larger percentage of the population will experience these as the baby boomer population ages. Our research is directed at understanding the processes mediating episodic memory, and the ways that these processes break down in normal aging. The prefrontal cortex (PFC) plays a critical role in encoding daily events and subsequent memory for them. We have proposed that right PFC subserves relatively heuristic processes and that left PFC (or left and right together) subserves more systematic processes. We propose to test the hypothesis that age-related decrements in episodic memory involve PFC dysfunction that disrupts processes typically subserved by left PFC, or the interaction between left and right PFC, more than those subserved by right PFC. Our research is guided by the source monitoring framework (SMF), which provides an evolving organizational structure for summarizing current understanding of these processes and a basis for generating new hypotheses. This approach has helped clarify fundamental theoretical issues in memory, including the nature of age-related changes. This proposal requests funds to continue our cognitive/behavioral and functional magnetic resonance imaging (fMRI) research on these issues. The project has three main goals: (1) To further clarify the nature of cognitive processes subserving episodic memory and to specify the ways they are (and are not) likely to be affected by aging; (2) To further develop methods for assessing the qualitative characteristics of memories and models of the subjective experience of remembering, and to assess changes in subjective experience with age; and (3) To identify the neural bases of source monitoring processes and specify those most affected by aging. Devising assessment procedures for identifying and quantifying episodic memory deficits, correlating them with other indices (such as neuropsychological tests), and developing remedial techniques for dealing with such deficits, will benefit from a more specific characterization of source monitoring processes and changes in those processes and their neural substrates with age. ? ?
Showing the most recent 10 out of 82 publications
