ArticleNeuroImage2022
Covariance-based vs. correlation-based functional connectivity dissociates healthy aging from Alzheimer disease.
Article in NeuroImage, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 22 citations in OpenAlex.
- Elucidating the neuropathological and molecular heterogeneity of amyloid beta and tau in Alzheimer's disease through machine learning and transcriptomic integration.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2026Article
- Sleep deprivation exhibits an age-dependent effect on infraslow global brain activity.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Functional network collapse in neurodegenerative disease.Nature communications · 2025Article
- Aging and the Spectral Properties of Brain Hemodynamics.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2025Article
- Functional Connectivity and Volumetrics Improve Outcome Prediction for Deep Brain Stimulation in Parkinson's Disease.Movement disorders clinical practice · 2025Article
- Basal forebrain global functional connectivity is preserved in asymptomatic presenilin-1 E280A mutation carriers: Results from the Colombia cohort.The journal of prevention of Alzheimer's disease · 2025Article
- Tell me why: A scoping review on the fundamental building blocks of fMRI-based network analysis.NeuroImage. Clinical · 2025Article
- Increasing hub disruption parallels dementia severity in autosomal dominant Alzheimer's disease.Network neuroscience (Cambridge, Mass.) · 2024Article
- Dissociable Effects of Alzheimer's Disease-Related Cognitive Dysfunction and Aging on Functional Brain Network Segregation.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2023Article
- Increasing hub disruption parallels dementia severity in autosomal dominant Alzheimer disease.bioRxiv : the preprint server for biology · 2023Article
- Brain network decoupling with increased serum neurofilament and reduced cognitive function in Alzheimer's disease.Brain : a journal of neurology · 2023Article
- Glioblastoma induces whole-brain spectral change in resting state fMRI: Associations with clinical comorbidities and overall survival.NeuroImage. Clinical · 2023Article
- Aging and Alzheimer's disease have dissociable effects on local and regional medial temporal lobe connectivity.Brain communications · 2023Article
- Resting state network mapping in individuals using deep learning.Frontiers in neurology · 2022Article
Corrections and comments
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Authors and funding
23 authors at 9 institutions in 4 countries.
Funding
Abstract
Prior studies of aging and Alzheimer disease have evaluated resting state functional connectivity (FC) using either seed-based correlation (SBC) or independent component analysis (ICA), with a focus on particular functional systems. SBC and ICA both are insensitive to differences in signal amplitude. At the same time, accumulating evidence indicates that the amplitude of spontaneous BOLD signal fluctuations is physiologically meaningful. We systematically compared covariance-based FC, which is sensitive to amplitude, vs. correlation-based FC, which is not, in affected individuals and controls drawn from two cohorts of participants including autosomal dominant Alzheimer disease (ADAD), late onset Alzheimer disease (LOAD), and age-matched controls. Functional connectivity was computed over 222 regions of interest and group differences were evaluated in terms of components projected onto a space of lower dimension. Our principal observations are: (1) Aging is associated with global loss of resting state fMRI signal amplitude that is approximately uniform across resting state networks. (2) Thus, covariance FC measures decrease with age whereas correlation FC is relatively preserved in healthy aging. (3) In contrast, symptomatic ADAD and LOAD both lead to loss of spontaneous activity amplitude as well as severely degraded correlation structure. These results demonstrate a double dissociation between age vs. Alzheimer disease and the amplitude vs. correlation structure of resting state BOLD signals. Modeling results suggest that the AD-associated loss of correlation structure is attributable to a relative increase in the fraction of locally restricted as opposed to widely shared variance.
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.