title: Age-associated changes in rhesus CNS composition identified by MRI.
abstract: Multispectral automated segmentation of MR images of the brains of 10 young (5-8 years), 10 middle-aged (12-17 years), and 11 old (21-27 years) female rhesus monkeys revealed age-associated changes in brain volume and composition. Total brain parenchymal volume (expressed as fraction of intracranial volume-%ICV) decreased at a linear rate of 0.3+/-0.04% ICV/year. Up to age approximately 15 years, this loss was almost entirely due to gray matter loss, with a compensatory increase in cerebrospinal fluid (CSF), and possibly some white matter. Brain tissue composition, expressed as the gray matter/white matter volume ratio confirmed that gray matter loss exceeded white matter loss, but the rate of decline in the gray/white ratio began to slow after approximately 15 years. Comparison of these age-associated changes in rhesus brain with those in humans suggest that the brain aging in rhesus is a good model of human brain aging, but occurs approximately 3-fold faster.
authors.affiliation: Department of Anatomy and Neurobiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
authors.forename: A H
authors.initials: AH
authors.lastname: Andersen
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Zhang
authors.forename: D M
authors.initials: DM
authors.lastname: Gash
authors.forename: M J
authors.initials: MJ
authors.lastname: Avison
mesh_terms: D000375:Aging / Q000134:cerebrospinal fluid / Q000473:pathology*; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000473:pathology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging