1. Adult brain aging investigated using BMC-mcDESPOT–based myelin water fraction imaging
- Author
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Richard G. Spencer, Susan M. Resnick, Luis E. Cortina, Christopher M. Bergeron, Abinand C. Rejimon, Luigi Ferrucci, Mustapha Bouhrara, and Nikkita Khattar
- Subjects
Male ,0301 basic medicine ,Aging ,Biology ,Article ,03 medical and health sciences ,Myelin ,0302 clinical medicine ,Nuclear magnetic resonance ,Body Water ,medicine ,Humans ,Magnetization transfer ,Brain aging ,Myelin Sheath ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,General Neuroscience ,Brain ,Magnetic resonance imaging ,Magnetic Resonance Imaging ,Middle age ,Large sample ,030104 developmental biology ,medicine.anatomical_structure ,Female ,Myelin water fraction ,Neurology (clinical) ,Geriatrics and Gerontology ,030217 neurology & neurosurgery ,Developmental Biology ,Diffusion MRI - Abstract
The relationship between regional brain myelination and aging has been the subject of intense study, with magnetic resonance imaging perhaps the most effective modality for elucidating this. However, most of these studies have used nonspecific methods to probe myelin content, including diffusion tensor imaging, magnetization transfer ratio, and relaxation times. In the present study, we used the BMC-mcDESPOT analysis, a direct and specific method for imaging of myelin water fraction (MWF), a surrogate of myelin content. We investigated age-related differences in MWF in several brain regions in a large cohort of cognitively unimpaired participants, spanning a wide age range. Our results indicate a quadratic, inverted U-shape, relationship between MWF and age in all brain regions investigated, suggesting that myelination continues until middle age followed by decreases at older ages. We also observed that these age-related differences vary across different brain regions, as expected. Our results provide evidence for nonlinear associations between age and myelin in a large sample of well-characterized adults, using a direct myelin content imaging method.
- Published
- 2020