Network segregation is associated with processing speed in the cognitively healthy oldest-ol
- University of Alabama at Birmingham, United States
- University of Miami, United States
- University of Florida, United States
- University of Arizona, United States
- University of Southern California, United States
Abstract
The brain is organized into systems and networks of interacting components. The functional connections among these components give insight into the brain's organization and may underlie some cognitive effects of aging. Examining the relationship between individual differences in brain organization and cognitive function in older adults who have reached oldest old ages with healthy cognition can help us understand how these networks support healthy cognitive aging. We investigated functional network segregation in 146 cognitively healthy participants aged 85+ in the McKnight Brain Aging Registry. We found that the segregation of the association system and the individual networks within the association system [the fronto-parietal network (FPN), cingulo-opercular network (CON) and default mode network (DMN)], has strong associations with overall cognition and processing speed. We also provide a healthy oldest-old (85+) cortical parcellation that can be used in future work in this age group. This study shows that network segregation of the oldest-old brain is closely linked to cognitive performance. This work adds to the growing body of knowledge about differentiation in the aged brain by demonstrating that cognitive ability is associated with differentiated functional networks in very old individuals representing successful cognitive aging.
Data availability
Code is available for node creation at https://github.com/Visscher-Lab/MBAR_oldestold_nodes and code and post processed data for statistical analyses and figures is available at https://github.com/Visscher-Lab/MBAR_segregation_paperBecause these data come from a select group of people who have lived to oldest-old ages, making them potentially identifiable, raw data is not available. More detailed data than the post processed data available online can be requested by submitting a request with explanation of intended use of the data to kmv@uab.edu. Requests are reviewed by a committee of principal investigators of the McKnight brain aging registry.
Article and author information
Author details
Funding
Evelyn F. McKnight Brain Research Foundation
- Ron A Cohen
- Bonnie E Levin
- Tatjana Rundek
- Gene E Alexander
- Kristina Visscher
National Institute of Health/National institute of Neurological Disorder and Stroke (T32NS061788-12 07/2008)
- Sara A Nolin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Informed consent was obtained from all participants and approval for the study was received from the Institutional Review Boards at each of the data collection sites including University of Alabama at Birmingham (IRB protocol X160113004), University of Florida (IRB protocol 201300162), University of Miami (IRB protocol 20151783), and University of Arizona (IRB protocol 1601318818).
Copyright
© 2025, Nolin et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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Network segregation is associated with processing speed in the cognitively healthy oldest-ol
eLife 14:e78076.
https://doi.org/10.7554/eLife.78076
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