Schaal, Stefan
Coauthors(s): Dagmar Sternad Department of Kinesiology, PennState University Rieko Osu Mitsuo Kawato Kawato Dynamic Brain Project (ERATO/JST)
USC
Computer Science and Neuroscience
3614 Watt Way HNB 103 Los Angeles, CA 90089-2520
http://www-slab.usc.edu

Functional brain activation in rhythmic and discrete movement

We investigated rhythmic and discrete flexion-extension wrist movement in an fMRI experiment with a 4 Tesla scanner. Subjects performed either continuous oscillations with the wrist at two different frequencies, or discrete flexion and extension movements with pseudo-random movement start times. Both conditions were executed either with or without metronome pacing, and even with the foot instead of the wrist in three subjects. SPM99 based data analysis, including averaging across 11 subjects provided highly statistically significant results. While rhythmic movement was confined to activations in primary contralateral motor cortices, supplementary motor cortex, and ipsilateral cerebellum, discrete movement elicited additional activation in contralateral premotor and parietal areas, and also in various ipsilateral cortical regions. These results indicate that discrete movements, even as simple as wrist flexion-extension movements, recruit significantly more cortical areas than rhythmic movement, and that discrete and rhythmic movement may have different movement generating principles in the brain.