4.5 Article

Age and amyloid-related alterations in default network habituation to stimulus repetition

Journal

NEUROBIOLOGY OF AGING
Volume 33, Issue 7, Pages 1237-1252

Publisher

ELSEVIER SCIENCE INC
DOI: 10.1016/j.neurobiolaging.2011.01.003

Keywords

Episodic memory; Functional MRI; Hippocampus; Amyloid; Aging

Funding

  1. Karolinska Institutet foundations [Fobi0794]
  2. Swedish Research Council
  3. Royal Swedish Academy of Sciences [FOAO7L501]
  4. European Union [FP7-PEOPLE-2007-4-1-IOF]
  5. National Institutes of Health [K24 AG035007, R01 AG027435-S1, P01AG036694, P50AG00513421]
  6. Alzheimer's Association [IIRG-06-27374, IIRG-08-90934]

Ask authors/readers for more resources

The neural networks supporting encoding of new information are thought to decline with age, although mnemonic techniques such as repetition may enhance performance in older individuals. Accumulation of amyloid-beta, one hallmark pathology of Alzheimer's disease (AD), may contribute to functional alterations in memory networks measured with functional magnetic resonance imaging (fMRI) prior to onset of cognitive impairment. We investigated the effects of age and amyloid burden on fMRI activity in the default network and hippocampus during repetitive encoding. Older individuals, particularly those with high amyloid burden, demonstrated decreased task-induced deactivation in the posteromedial cortices during initial stimulus presentation and failed to modulate fMRI activity in response to repeated trials, whereas young subjects demonstrated a stepwise decrease in deactivation with repetition. The hippocampus demonstrated similar patterns across the groups, showing task-induced activity that decreased in response to repetition. These findings demonstrate that age and amyloid have dissociable functional effects on specific nodes within a distributed memory network, and suggest that functional brain changes may begin far in advance of symptomatic Alzheimer's disease. (C) 2012 Elsevier Inc. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available