Extracranial magnetoencephalographic activity was separately recorded (25 channels) from bilateral primary sensorimotor cortex (M1-S1) of normal right-handers during unilateral finger movements. Standard dipole analysis indicated only a contralateral M1-S1 source for first movement-evoked field (MEF1) peaking at about 115 ms after electromyographic onset. However, the subtraction of the magnetic field generated by this source from the recorded magnetic field disclosed a low-amplitude ipsilateral central-parietal MEFI that was explained by an ipsilateral M1-S1 source.
- Finger movement
- Hemispheric functional asymmetry
- Human cerebral cortex
- Primary sensorimotor cortex (M1-S1)
ASJC Scopus subject areas