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bioRxiv · 10.1101/2025.07.01.662626

Towards Precision Functional Brain Network Mapping in Parkinsons Disease

Chernicky, J.·Dworetsky, A.·Grossen, S.·Carr, E.·Eid, A.·Campbell, M. C.·Gratton, C.
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Abstract

BackgroundParkinsons disease (PD) is a complex neurodegenerative condition that leads to widespread disruption of large-scale brain networks and is further complicated by substantial individual variability in symptomology, progression rates, and treatment response. Consequently, the investigation of individual differences in networks measured via resting state functional connectivity (RSFC) may provide insight. However, most RSFC studies are unable to identify interindividual differences due to poor reliability and group average network definitions. "Precision" RSFC addresses these shortcomings through extended data collection, strict denoising, and individual network definition, but remains untested in PD. ObjectivesTo evaluate the feasibility and reliability of precision RSFC studies in PD. MethodsWe collected >100 minutes of RSFC data from 20 PD and 6 healthy controls participants. We evaluated the level of motion, reliability and stability of RSFC measures in each participant and contrasted these measures between the PD and HC groups, as well as compared to a conventional 5 minutes of RSFC data. In addition, we created individualized brain network measures in PD participants to establish feasibility in this population. ResultsUsing precision methods, the PD group produced reliable and stable RSFC measures of brain networks of similar quality to healthy controls and substantially better than conventional methods. Individualized network maps from individuals with PD demonstrate differences from group averages and from each other, including in key motor systems. ConclusionPrecision RSFC is feasible and reliable in individuals with PD. This approach holds promise for advancing personalized diagnostics and identifying brain-based biomarkers underlying clinical variability in PD.

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Chernicky, J., Dworetsky, A., Grossen, S., Carr, E., Eid, A., Campbell, M. C., Gratton, C.. 2025-07-07. Towards Precision Functional Brain Network Mapping in Parkinsons Disease. https://doi.org/10.1101/2025.07.01.662626

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