Amyloid Plaques Disrupt Resting State Default Mode Network Connectivity in Cognitively Normal Elderly
Yvette I. Sheline, Marcus E. Raichle, Abraham Z. Snyder, John C. Morris, Denise Head, Suzhi Wang, Mark A. Mintun
Biological Psychiatry October 15, 2009 DOI: 10.1016/j.biopsych.2009.08.024 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 103 |
| Population | Cognitively normal participants and Alzheimer's disease patients |
| Topics | Default mode network |
| Citations | 608 |
| Key findings | Cognitively normal participants with brain amyloid deposition showed altered resting-state functional connectivity in the same regions and direction as Alzheimer's disease patients. |
Abstract
BackgroundImportant functional connections within the default mode network (DMN) are disrupted in Alzheimer's disease (AD), likely from amyloid-beta (Abeta) plaque-associated neuronal toxicity. Here, we sought to determine if pathological effects of Abeta amyloid plaques could be seen, even in the absence of a task, by examining functional connectivity in cognitively normal participants with and without preclinical amyloid deposition.MethodsParticipants with Alzheimer's disease (AD) (n = 35) were compared with 68 cognitively normal participants who were further subdivided by positron emission tomography (PET) Pittsburgh Compound-B (PIB) imaging into those without evidence of brain amyloid (PIB-) and those with brain amyloid (PIB+) deposition.ResultsResting state functional magnetic resonance imaging (fMRI) demonstrated that, compared with the PIB- group, the PIB+ group differed significantly in functional connectivity of the precuneus to hippocampus, parahippocampus, anterior cingulate, dorsal cingulate, gyrus rectus, superior precuneus, and visual cortex. These differences were in the same regions and in the same direction as differences found in the AD group.ConclusionsThus, before any manifestations of cognitive or behavioral changes, there were differences in resting state connectivity in cognitively normal subjects with brain amyloid deposition, suggesting that early manifestation of Abeta toxicity can be detected using resting state fMRI.