Cortical control of human motoneuron firing during isometric contraction.

@article{Salenius1997CorticalCO,
  title={Cortical control of human motoneuron firing during isometric contraction.},
  author={Stephan Salenius and Karin Portin and Matti Kajola and Riitta Salmelin and Riitta Hari},
  journal={Journal of neurophysiology},
  year={1997},
  volume={77 6},
  pages={
          3401-5
        }
}
We recorded whole scalp magnetoencephalographic (MEG) signals simultaneously with the surface electromyogram from upper and lower limb muscles of six healthy right-handed adults during voluntary isometric contraction. The 15- to 33-Hz MEG signals, originating from the anterior bank of the central sulcus, i.e., the primary motor cortex, were coherent with motor unit firing in all subjects and for all muscles. The coherent cortical rhythms originated in the hand motor area for upper limb muscles… 

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