Physical activity and neural correlates of aging: A combined TMS/fMRI study

• Published in: Behavioural brain research 2011-09, Vol.222 (1), p.158-168
• Main Authors: McGregor, Keith M., Zlatar, Zvinka, Kleim, Erin, Sudhyadhom, Atchar, Bauer, Andrew, Phan, Stephanie, Seeds, Lauren, Ford, Anastasia, Manini, Todd M., White, Keith D., Kleim, Jeffrey, Crosson, Bruce
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Adults; Aerobics; Aged; Aged, 80 and over; Aging; Aging - physiology; Area Under Curve; Bacteria, Aerobic - physiology; Behavioral psychophysiology; Biological and medical sciences; Brain; Brain - blood supply; Brain - physiology; Brain Mapping; Cerebral hemispheres; Cortex (motor); Electromyography; Evoked Potentials, Motor - physiology; Exercise; Female; Fitness; fMRI; Functional magnetic resonance imaging; Fundamental and applied biological sciences. Psychology; Gerontology; Handedness; Humans; Image Processing, Computer-Assisted - methods; Inhibition; Interhemispheric communication; Magnetic Resonance Imaging - methods; Male; Middle Aged; Motor Activity - physiology; Movement; Muscle Contraction - physiology; Oxygen - blood; Physical activity; Physical training; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Reaction Time - physiology; Scanning; Seasons; Stimuli; Surveys and Questionnaires; TMS; Transcranial magnetic stimulation; Transcranial Magnetic Stimulation - methods; Young Adult
• ISSN: 0166-4328; 1872-7549
• DOI: 10.1016/j.bbr.2011.03.042

► We compare ipsilateral motor activity across age groupings using fMRI and TMS. ► Groups consist of young adults, physically active elderly adults, and sedentary elderly adults. ► Physically active older adults show ipsilateral motor patterns similar to younger adults. ► Ipsilateral silent period inversely correlates with fMRI activity in ipsilateral motor cortex. 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.