Schedule of Events | Symposia

Distinct brain age gradients reflect diverse neurobiological hierarchies.

Poster Session E - Monday, March 31, 2025, 2:30 – 4:30 pm EDT, Back Bay Ballroom/Republic Ballroom

Nicholas Riccardi¹ (riccardn@email.sc.edu), Sarah Newman-Norlund¹, Julius Fridriksson¹, Chris Rorden¹, Leonardo Bonilha²; ¹University of South Carolina, ²School of Medicine Columbia

Introduction: "Brain age" is a biomarker of brain health, often used as a single global metric. However, this global approach may overlook the influence of nonuniformly distributed neuroaxes (gene expression, cerebral blood flow, etc.). Here, we used a region-specific brain age approach to investigate spatial brain aging patterns in 167 neurologically intact adults (aged 20–79 years) and related these patterns to known neuroaxes and behavioral performance, including cognitive status. Methods: T1-weighted MR images were analyzed with volBrain’s BrainStructureAges to estimate brain ages for 104 cortical regions. Regional brain age gaps (regiBAG) were calculated as the difference between estimated and chronological ages. Behavioral measures included MoCA, visual acuity, hearing, balance, and gait speed. Exploratory factor analysis identified six regiBAG patterns explaining 95% of variance. Linear regression related these patterns to region-specific rankings from 10 neuroaxes, and stepwise regression linked participant-level regiBAG patterns to behavior while controlling for age, sex, and education with FDR correction. Results: Regional loading scores from the six factors significantly aligned with neuroaxes (R² range=.05–.56, p’s<.05), with gene expression being the strongest predictor. Participant-level regiBAG patterns predicted behavioral performance beyond age, sex, and education (adj. R² range=.07–.59, p’s<.002). For example, greater regiBAG in the ventral visual stream related to worse visual acuity, and greater regiBAG in right temporoparietal regions related to lower MoCA scores. Global brain age did not predict behavior. Conclusion: Spatial patterns of brain aging align with hierarchical neurobiological gradients and have distinct behavioral correlates, offering a more nuanced framework than global brain age.

Topic Area: NEUROANATOMY