title: Physical activity and neural correlates of aging: a combined TMS/fMRI study.
abstract: Aerobic exercise has been suggested to ameliorate aging-related decline in humans. Recently, evidence has indicated chronological aging is associated with decreases in measures of interhemispheric inhibition during unimanual movements, but that such decreases may be mitigated by long-term physical fitness. The present study investigated measures of ipsilateral (right) primary motor cortex activity during right-hand movements using functional magnetic resonance imaging and transcranial magnetic stimulation (TMS). Healthy, right-handed participant groups were comprised of 12 sedentary older adults, 12 physically active older adults, and 12 young adults. Active older adults and younger adults evidenced longer ipsilateral silent periods (iSP) and less positive BOLD of ipsilateral motor cortex (iM1) as compared to sedentary older adults. Across groups, duration of iSP from TMS was inversely correlated with BOLD activity in iM1 during unimanual movement. These findings suggest that increased physical activity may have a role in decreasing aging-related losses of interhemispheric inhibition.
authors: Department of Veterans Affairs Rehabilitation Research and Development Brain Rehabilitation Research Center at the Malcom Randall VA Medical Center, United States. kmcgrego@phhp.ufl.edu
authors: Keith M
authors: KM
authors: McGregor
authors: Zvinka
authors: Z
authors: Zlatar
authors: Erin
authors: E
authors: Kleim
authors: Atchar
authors: A
authors: Sudhyadhom
authors: Andrew
authors: A
authors: Bauer
authors: Stephanie
authors: S
authors: Phan
authors: Lauren
authors: L
authors: Seeds
authors: Anastasia
authors: A
authors: Ford
authors: Todd M
authors: TM
authors: Manini
authors: Keith D
authors: KD
authors: White
authors: Jeffrey
authors: J
authors: Kleim
authors: Bruce
authors: B
authors: Crosson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D019540:Area Under Curve; D001420:Bacteria, Aerobic / Q000502:physiology; D001921:Brain / Q000098:blood supply* / Q000502:physiology*; D001931:Brain Mapping; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009068:Movement; D009119:Muscle Contraction / Q000502:physiology; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology; D012621:Seasons; D011795:Surveys and Questionnaires; D050781:Transcranial Magnetic Stimulation / Q000379:methods; D055815:Young Adult
chemical_list: D010100:Oxygen