Dataset Information

Diminished Learning Over Repeated Exposures (LORE) in preclinical Alzheimer's disease.

ABSTRACT:

Introduction

We determine whether diminished Learning Over Repeated Exposures (LORE) identifies subtle memory decrements in cognitively unimpaired (CU) older adults with Alzheimer's disease (AD) biomarker burden.

Methods

Ninety-four CU participants (mean age = 77.6 ± 5.02) completed a challenging associative memory test, at home, monthly, for up to 1 year (mean = 9.97 months) on a study-issued iPad. Learning curves for face-name memory were computed for two versions completed monthly: same face-name pairs (A-A-A) and alternate face-name pairs (B-C-D). Positron emission tomography (PET) imaging characterized global amyloid (Pittsburgh Compound-B (PiB); amyloid beta (Aβ)+/-) and regional tau burden (flortaucipir).

Results

Diminished LORE for same (but not alternate) face-name pairs was associated with greater amyloid and tau burden. Aβ+/- group differences for same face-name pairs emerged by the fourth exposure and was of medium-to-large magnitude (Cohen's d = 0.66; 95% confidence interval [CI] = 0.25-1.08).

Discussion

Subtle decrements in learning related to AD pathological burden in CU are detectable over short time-intervals (ie, months). Implications for prevention trial design are discussed.

SUBMITTER: Samaroo A

PROVIDER: S-EPMC7784542 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

Diminished Learning Over Repeated Exposures (LORE) in preclinical Alzheimer's disease.

Samaroo Aubryn A Amariglio Rebecca E RE Burnham Samantha S Sparks Paige P Properzi Michael M Schultz Aaron P AP Buckley Rachel R Johnson Keith A KA Sperling Reisa A RA Rentz Dorene M DM Papp Kathryn V KV

Alzheimer's & dementia (Amsterdam, Netherlands) 20200101 1

<h4>Introduction</h4>We determine whether diminished Learning Over Repeated Exposures (LORE) identifies subtle memory decrements in cognitively unimpaired (CU) older adults with Alzheimer's disease (AD) biomarker burden.<h4>Methods</h4>Ninety-four CU participants (mean age = 77.6 ± 5.02) completed a challenging associative memory test, at home, monthly, for up to 1 year (mean = 9.97 months) on a study-issued iPad. Learning curves for face-name memory were computed for two versions completed mont ...[more]

PMID: 33426266

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Dataset Information

Diminished Learning Over Repeated Exposures (LORE) in preclinical Alzheimer's disease.

Introduction

Methods

Results

Discussion

Publications

Diminished Learning Over Repeated Exposures (LORE) in preclinical Alzheimer's disease.

Similar Datasets

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