title: Associations between age, motor function, and resting state sensorimotor network connectivity in healthy older adults.
abstract: Aging is associated with impaired motor performance across a range of tasks. Both primary neural representations of movement and potential compensatory cognitive mechanisms appear to be disrupted in older age. Here we determined how age is associated with resting state sensorimotor functional connectivity, and whether connectivity strength is associated with motor performance. We investigated the association between age and resting state functional connectivity of several sensorimotor networks in 191 healthy older, right-handed individuals. Regions of interest were defined in the left motor cortex, left putamen, and right cerebellar lobules V and VIII. Analyses were adjusted for head motion, gray matter volume, diastolic blood pressure, and smoker status; we then evaluated whether connectivity is associated with participants' manual motor performance. We found both increased and decreased connectivity within portions of the motor cortical and cerebellar networks after adjusting for covariates. We observed that connectivity increased with age for the motor cortex and cerebellar lobule VIII with the putamen, providing evidence of greater interactivity across networks with age. Higher tapping frequency and greater grip force were associated with stronger connectivity between the motor cortex during resting state, putamen, cerebellar lobule VIII and the insular cortex, suggesting that greater network interactivity may protect against age declines in performance.
authors.affiliation: School of Kinesiology, University of Michigan, Ann Arbor, USA; Department of Psychology, University of Michigan, Ann Arbor, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, USA. Electronic address: rseidler@umich.edu.
authors.forename: Rachael
authors.initials: R
authors.lastname: Seidler
authors.affiliation: School of Kinesiology, University of Michigan, Ann Arbor, USA.
authors.forename: Burak
authors.initials: B
authors.lastname: Erdeniz
authors.affiliation: School of Kinesiology, University of Michigan, Ann Arbor, USA.
authors.forename: Vincent
authors.initials: V
authors.lastname: Koppelmans
authors.affiliation: International Normal Aging and Plasticity Imaging Center (INAPIC), University of Zurich, Switzerland; University Research Priority Program "Dynamics of Healthy Aging", University of Zurich, Switzerland.
authors.forename: Sarah
authors.initials: S
authors.lastname: Hirsiger
authors.affiliation: International Normal Aging and Plasticity Imaging Center (INAPIC), University of Zurich, Switzerland; University Research Priority Program "Dynamics of Healthy Aging", University of Zurich, Switzerland.
authors.forename: Susan
authors.initials: S
authors.lastname: Mérillat
authors.affiliation: International Normal Aging and Plasticity Imaging Center (INAPIC), University of Zurich, Switzerland; University Research Priority Program "Dynamics of Healthy Aging", University of Zurich, Switzerland; Division of Neuropsychology, University of Zurich, Switzerland.
authors.forename: Lutz
authors.initials: L
authors.lastname: Jäncke
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology*; D012146:Rest / Q000502:physiology
keywords: Cerebellum; Grip force; Healthy aging; MRI; Motor cortex; Resting state functional connectivity; Tapping speed