We used functional magnetic resonance imaging (fMRI) to record human brain activity during slow (30 RPM), fast (60 RPM), passive (30 RPM), and variable rate pedaling. Ten healthy adults participated. After identifying regions of interest, the intensity and volume of brain activation in each region was calculated and compared across conditions (p < .05). Results showed that the primary sensory and motor cortices (S1, M1), supplementary motor area (SMA), and cerebellum (Cb) were active during pedaling. The intensity of activity in these areas increased with increasing pedaling rate and complexity. The Cb was the only brain region that showed significantly lower activity during passive as compared with active pedaling. We conclude that M1, S1, SMA, and Cb have a role in modifying continuous, bilateral, multijoint lower extremity movements. Much of this brain activity may be driven by sensory signals from the moving limbs.
Mehta is with the Department of Physical Therapy and the Department of Biomedical Engineering, Marquette University, Milwaukee, WI. Verber is with the Clinical and Translational Science Institute, Medical College of Wisconsin, Milwaukee, WI. Wieser and Schindler-Ivens are with the Department of Physical Therapy, Marquette University, Milwaukee, WI. Schmit is with the Department of Biomedical Engineering, Marquette University, Milwaukee, WI.