Effects of Aging on Memory for Source of Information

点击翻译按钮获取中文摘要

Program Director/Principal Investigator(Last, First, Middle): Johnson, Marcia, K. PROJECT SUMMARY (See instructions): Mental experiences involve active information from various sources (perceptions, imaginations, inferences, memories, emotions). Because there is overlap in the features arising from different sources and the processes that encode, revive, and evaluate features with respect to their source are not perfect, misattributions can occur (perceptual illusions, memory distortions, false memories, confabulations). Our goal is understanding the cognitive processes and conditions that account for true and false episodic (autobiographical) memories: source memory processes that encode features and associate (bind) them into complex memories, and that revive and evaluate them later (i.e., as we make attributions).Our research is guided by the Source Monitoring Framework (SMF), which identifies cognitive processes, types of information (e.g., features), and associated brain correlates that together serve normal source memory and provides a focus for investigating how source memory might be impaired. In particular, our research program is directed at understanding how source monitoring processes are affected by normal aging. Evidence from brain damaged patients and from neuroimaging suggests that prefrontal cortex (PFC) is critical for encoding, reviving, and evaluating memories, and that a critical function of PFC is to modulate activity in other brain regions (e.g., hippocampus, posterior representational areas) involved in memory. Furthermore, there is increasing evidence that age-related changes in function in PFC contribute to age-related declines in episodic memory. Using cognitive behavioral and functional magnetic resonance imaging (fMRI) methods, the proposed project has three main goals: (1) To further characterize age-related differences in the cognitive processes subserving source memory, that is, those processes that affect the quality of encoding, revival, and evaluation of episodic memories; (2) To identify distinct neural bases of specific cognitive functions important for source memory, how they interact, and how they are affected by aging; (3) To further clarify the relation, at both cognitive and neural levels, between objective and subjective measures of source memory and how they change withage. RELEVANCE (See instructions): Among the consequences of normal aging, one of the most distressing is decline in memory. The associated loss of productivity, physical health, and sense of well-being will create an increasing number of critical economic and public health issues as the US population grows disproportionately older.This proposal is directed at understanding the neural mechanisms that underlie changes in memory function with age. PROJECT/