Article

Brain activation during human finger extension and flexion movements

Department of Biomedical Engineering/ND20, The Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA; Department of Radiology, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA; Department of Rehabilitation Medicine, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 USA
Brain Research (impact factor: 2.73). 03/2000; DOI:10.1016/S0006-8993(99)02385-9 pp.291-300

ABSTRACT Corticospinal projections to the motor neuron pool of upper-limb extensor muscles have been reported to differ from those of the flexor muscles in humans and other primates. The influence of this difference on the central nervous system control for extension and flexion movements is unknown. Cortical activation during thumb extension and flexion movements of eight human volunteers was measured using functional magnetic resonance imaging (fMRI), which detects signal changes caused by an alteration in the local blood oxygenation level. Although the relative activity of the extensor and flexor muscles of the thumb was similar, the brain volume activated during extension was substantially larger than that during flexion. These fMRI results were confirmed by measurements of EEG-derived movement-related cortical potential. Higher brain activity during thumb extension movement may be a result of differential corticospinal, and possibly other pathway projections to the motoneuron pools of extensor and flexor muscles of upper the extremities.

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Keywords

central nervous system control
 
detects signal changes
 
EEG-derived movement-related cortical potential
 
flexion
 
flexion movements
 
flexor muscles
 
fMRI results
 
functional magnetic resonance imaging
 
Higher brain activity
 
human volunteers
 
humans
 
local blood oxygenation level
 
motoneuron pools
 
pathway projections
 
relative activity
 
upper-limb extensor muscles