Diffusion imaging markers of accelerated aging of the lower cingulum in subjective cognitive decline

• DOI: 10.3389/fneur.2024.1360273
• Publication Date: 2024-05-09T04:32:05Z
• Authors: Ryn Flaherty; Yu Veronica Sui; Arjun V. Masurkar; Rebecca A. Betensky; Henry Rusinek; Mariana Lazar
• Keywords: Cingulum (brain); Cognitive Decline; Cognitive aging

Introduction Alzheimer’s Disease (AD) typically starts in the medial temporal lobe, then develops into a neurodegenerative cascade which spreads to other brain regions. People with subjective cognitive decline (SCD) are more likely develop dementia, especially presence of amyloid pathology. Thus, we were interested white matter microstructure lobe SCD, specifically lower cingulum bundle that leads hippocampus. Diffusion tensor imaging (DTI) has been shown differentiate SCD participants who will progress mild impairment from those not. However, biology underlying these DTI metrics is unclear, and results have inconsistent. Methods To better characterize this region, applied cognitively normal Cam-CAN database over age 55 testing diffusion MRI available ( N = 325, 127 SCD). was processed generate regional voxel-wise values bilateral matter, while T1-weighted volume cortical thickness entorhinal cortex, pole, Results had thinner cortex right pole. No between-group differences noted for any microstructural cingulum. correlations delayed story recall significant all but not controls, interaction effect. Additionally, group showed an accelerated aging effect MD, AxD, RD. Discussion The profiles observed both effects suggestive mixed neuroinflammatory Left thinning correlated decreased FA increased RD, demyelination. also This may reflect combined pathologies implicated early AD. sensitive than associations between memory, age. pathology increase sensitivity variations cognition.