Subjective perception of memory loss is very common in older adults, though there is no straightforward relationship between cognitive complaints and performance as assessed with conventional neuropsychological instruments. We have identified a group of nondepressed, healthy older adults with significant cognitive complaints (particularly involving memory) despite intact functioning on extensive neuropsychological testing (referred to as the Cognitive Complaint, CC, group). These individuals show structural brain changes intermediate between those seen in amnestic mild cognitive impairment (MCI) and normal elders and may represent a "pre-MCI" population. Thus, cognitive complaints in otherwise healthy, nondepressed older adults may indicate underlying neurodegenerative changes that could provide an earlier therapeutic opportunity than MCI. The realization of this potential, however, will require an improved understanding of the relationship between self-appraised memory and actual performance, as well as the factors that influence this relationship. Our main goal is to use novel paradigms to test hypotheses regarding the nature and clinical significance of cognitive complaints in a demographically diverse group of approximately 250 older adults with varying degrees of cognitive complaints and impairment. We propose that cognitive complaints reflect subtle abnormalities not readily detected by conventional tools, and that tasks developed using paradigms other than traditional episodic memory may provide more sensitive criteria by which to test the relationship between subjective and objective memory. We will enroll nondepressed, nondemented older adults meeting inclusion criteria and classify them as healthy control, CC, or MCI using the procedures described in the proposal. We predict that neuropsychologically intact older adults with marked cognitive complaints, but not those without complaints, will show: (1) mild performance deficits on prospective and procedural metamemory tasks despite intact performance on conventional tools;(2) lower memory self-efficacy and reduced use of mnemonic strategies and compensatory behaviors;and (3) increased risk of conversion to MCI over time. Our long-term goals are to evaluate the diagnostic and predictive utility of cognitive complaints and identify variables that best predict progression from pre-MCI to MCI and eventually dementia. We also hope to expand the cohort in the future and implement a cognitive intervention for pre-MCI that targets behaviors and beliefs that were found to be relevant in the proposed study and that are potentially modifiable, such as enhancing the use of memory strategies and self-efficacy. The proposed study will have the advantages of a community-based sample, longitudinal design, and psychometric approach to the assessment of cognitive complaints. NIH support of this proposal will provide the applicant with the experience necessary to transition to an independent investigator. Importantly, findings will advance scientific understanding of memory self-appraisals and the cognitive changes that precede the onset of dementia, with important implications for early diagnosis and clinical care.
Alzheimer's disease (AD) is a major global public health problem that seriously impacts patients, their families, and society;an understanding of normal and abnormal memory processes in the early presentation of AD is a critical research priority that will facilitate detection of predementia conditions. The proposed study will advance basic scientific understanding of memory self-appraisals and the cognitive changes that precede the onset of AD, with significant implications for early diagnosis, clinical care, and intervention. Additionally, this study will meet important public health needs by increasing minority access to research and improving the ability to differentiate individuals at high risk for progressive cognitive decline from the "worried well," who can be reassured and followed.
|Rabin, Laura A; Chi, Susan Y; Wang, Cuiling et al. (2014) Prospective memory on a novel clinical task in older adults with mild cognitive impairment and subjective cognitive decline. Neuropsychol Rehabil 24:868-93|