title: Longitudinal alterations to brain function, structure, and cognitive performance in healthy older adults: A fMRI-DTI study.
abstract: Cross-sectional research has shown that older adults tend to have different frontal cortex activation patterns, poorer brain structure, and lower task performance than younger adults. However, relationships between longitudinal changes in brain function, brain structure, and cognitive performance in older adults are less well understood. Here we present the results of a longitudinal, combined fMRI-DTI study in cognitive normal (CN) older adults. A two time-point study was conducted in which participants completed a task switching paradigm while fMRI data was collected and underwent the identical scanning protocol an average of 3.3 years later (SD=2 months). We observed longitudinal fMRI activation increases in bilateral regions of lateral frontal cortex at time point 2. These fMRI activation increases were associated with longitudinal declines in WM microstructure in a portion of the corpus callosum connecting the increasingly recruited frontal regions. In addition, the fMRI activation increase in the left VLPFC was associated with longitudinal increases in response latencies. Taken together, our results suggest that local frontal activation increases in CN older adults may in part reflect a response to reduced inter-hemispheric signaling mechanisms.
authors: Department of Anatomy and Neurobiology, USA.
authors: Jonathan G
authors: JG
authors: Hakun
authors: Department of Anatomy and Neurobiology, USA.
authors: Zude
authors: Z
authors: Zhu
authors: Department of Anatomy and Neurobiology, USA.
authors: Christopher A
authors: CA
authors: Brown
authors: Department of Rehabilitation Sciences, USA.
authors: Nathan F
authors: NF
authors: Johnson
authors: Department of Anatomy and Neurobiology, USA; Magnetic Resonance Imaging and Spectroscopy Center, USA; Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536, USA. Electronic address: brian.gold@uky.edu.
authors: Brian T
authors: BT
authors: Gold
mesh_terms: D000375:Aging / Q000473:pathology* / Q000502:physiology*; D001921:Brain / Q000473:pathology* / Q000502:physiology*; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D066127:White Matter / Q000473:pathology / Q000502:physiology
keywords: Aging; Diffusion tensor imaging; Longitudinal; fMRI