Memory consolidation in aging and MCI after 1 week.
OBJECTIVE
To assess consolidation in amnestic mild cognitive impairment (aMCI), controlling for differences in initial learning and using a protracted delay period for recall.


METHODS
15 individuals with aMCI were compared with 15 healthy older adult controls on a story learning task. Subjects were trained to criteria to equalize initial learning across subjects. Recall was tested at both the 30-min typically used delay and a 1-week delay used to target consolidation.


RESULTS
Using repeated measures ANOVAs adjusted for age, we found group × time point interactions across the entire task between the final trial and 30-min delay, and again between the 30-min and 1-week delay periods, with aMCI having greater declines in recall as compared with controls. Significant group main effects were also found, with aMCI recalling less than controls.


CONCLUSIONS
Consolidation was impaired in aMCI as compared with controls. Our findings indicate that aMCI-related performance typically measured at 30 min underestimates aMCI-associated memory deficits. This is the first study to isolate consolidation by controlling for initial learning differences and using a protracted delay period to target consolidation in an aMCI sample.
Memory and Aging Center, Department of Neurology, University of California, San Francisco.
Christine M
CM
Walsh
Memory and Aging Center, Department of Neurology, University of California, San Francisco.
Sarah
S
Wilkins
Memory and Aging Center, Department of Neurology, University of California, San Francisco.
Brianne Magouirk
BM
Bettcher
Department of Clinical Neurology, University of Oxford.
Christopher R
CR
Butler
Memory and Aging Center, Department of Neurology, University of California, San Francisco.
Bruce L
BL
Miller
Memory and Aging Center, Department of Neurology, University of California, San Francisco.
Joel H
JH
Kramer
D000368:Aged; D000375:Aging / Q000523:psychology*; D000647:Amnesia / Q000150:complications*; D060825:Cognitive Dysfunction / Q000150:complications / Q000523:psychology*; D005260:Female; D006801:Humans; D007858:Learning; D008297:Male; D008568:Memory; D011939:Mental Recall