Neural compensation in older people with brain amyloid-? deposition.
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ABSTRACT:
SUBMITTER: Elman JA
PROVIDER: S-EPMC4177011 | biostudies-literature | 2014 Oct
REPOSITORIES: biostudies-literature
Publications
Neural compensation in older people with brain amyloid-β deposition.
Elman Jeremy A JA Oh Hwamee H Madison Cindee M CM Baker Suzanne L SL Vogel Jacob W JW Marks Shawn M SM Crowley Sam S O'Neil James P JP Jagust William J WJ
Nature neuroscience 20140914 10
Recruitment of extra neural resources may allow people to maintain normal cognition despite amyloid-β (Aβ) plaques. Previous fMRI studies have reported such hyperactivation, but it is unclear whether increases represent compensation or aberrant overexcitation. We found that older adults with Aβ deposition had reduced deactivations in task-negative regions, but increased activation in task-positive regions related to more detailed memory encoding. The association between higher activity and more ...[more]
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