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bioRxiv · 10.1101/109181

Age-related changes in spatial and temporal features of resting state fMRI

Vij, S. G.·Nomi, J.·Dajani, D. R.·Uddin, L. Q.
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Abstract

Development and aging are associated with functional changes in the brain across the lifespan. These changes can be detected in spatial and temporal features of resting state functional MRI (rs-fMRI) data. Independent vector analysis (IVA) is a whole-brain multivariate approach that can be used to comprehensively assess these changes in spatial and temporal features. We present a multi-dimensional approach to assessing age-related changes in spatial and temporal features of statistically independent components identified by IVA in a cross-sectional lifespan sample (ages 6-85 years). We show that while large-scale brain network configurations remain consistent throughout the lifespan, changes continue to occur in both local organization and in the spectral composition of these functional networks. We show that the spatial extent of functional networks decreases with age, but with no significant change in the peak functional loci of these networks. Additionally, we show differential age-related patterns across the frequency spectrum; lower frequency correlations decrease across the lifespan whereas higher-frequency correlations increase. These changes indicate an increasing stability of networks with age. In addition to replicating results from previous studies, the current results uncover new aspects of functional brain network changes across the lifespan that are frequency band-dependent.

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Vij, S. G., Nomi, J., Dajani, D. R., Uddin, L. Q.. 2017-02-17. Age-related changes in spatial and temporal features of resting state fMRI. https://doi.org/10.1101/109181

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