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Functional and Pathological Correlates of Judgments of Learning in Cognitively Unimpaired Older Adults.

ABSTRACT: Judgments of learning (JOL) pertain to introspective metamemory processes evaluating how well information is learned. Using a functional magnetic resonance imaging (fMRI) task, we investigated the neural substrates of JOL predictions in a group of 105 cognitively unimpaired older adults from the Harvard Aging Brain Study. Associations of JOL performance and its neural correlates with amyloid-? (A?) and tau pathology, two proteinopathies associated with Alzheimer's disease (AD) and aging, were also examined. We found that trials judged as learned well relative to trials judged as learned less well (high JOL?>?low JOL) engaged the ventromedial prefrontal cortex and precuneus, among other midline regions, in addition to bilateral hippocampi. In this cohort of older adults, greater levels of entorhinal tau deposition were associated with overestimation of memory performance and with lower fMRI signal in midline regions during predicted memory success. No associations with A? were found. The findings suggest that tau pathology in unimpaired older adults may play a role in altered metamemory processes. We discuss our findings in light of the hypothesis that JOLs are partially dependent on a process involving attempts to retrieve a correct answer from memory, as well as implications for clinical research investigating unawareness of memory performance (i.e., anosognosia) in patients with AD dementia.

SUBMITTER: d'Oleire Uquillas F

PROVIDER: S-EPMC7132950 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Functional and Pathological Correlates of Judgments of Learning in Cognitively Unimpaired Older Adults.

d'Oleire Uquillas Federico F Jacobs Heidi I L HIL Schultz Aaron P AP Hanseeuw Bernard J BJ Buckley Rachel F RF Sepulcre Jorge J Pascual-Leone Alvaro A Donovan Nancy J NJ Johnson Keith A KA Sperling Reisa A RA Vannini Patrizia P

Cerebral cortex (New York, N.Y. : 1991) 20200301 3

Judgments of learning (JOL) pertain to introspective metamemory processes evaluating how well information is learned. Using a functional magnetic resonance imaging (fMRI) task, we investigated the neural substrates of JOL predictions in a group of 105 cognitively unimpaired older adults from the Harvard Aging Brain Study. Associations of JOL performance and its neural correlates with amyloid-β (Aβ) and tau pathology, two proteinopathies associated with Alzheimer's disease (AD) and aging, were al ...[more]

PMID: 31696223

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Dataset Information

Functional and Pathological Correlates of Judgments of Learning in Cognitively Unimpaired Older Adults.

Publications

Functional and Pathological Correlates of Judgments of Learning in Cognitively Unimpaired Older Adults.

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