Our results suggest, therefore, that the sources for s1/4 and those for MRCFs are based on the activations of different neuronal populations in the same precentral motor region. In addition, differences in source orientation between

s5 and components of MRCFs were apparent in the horizontal and sagittal planes (Table ​(Table22). Table Inhibitors,research,lifescience,medical 2 Difference in orientation among components of MRCFs and SEFs Sources in other brain regions The magnetic fields responsible for the MRCFs were subtracted from the recorded magnetic fields. In the residual fields, components showing a dipolar pattern of activity were explored over the hemispheres. Table ​Table33 summarizes these results. The regions related to visual processing (or movement monitoring) or somatosensory processing that might be attributable to the Inhibitors,research,lifescience,medical planning and execution of movement exhibited dipolar pattern of activations across movement time. These responses consist of slow premovement dipole activities with nearly the same

onset times as those observed for the MF component. Inhibitors,research,lifescience,medical Thereafter, however, no phasic alternation of peaks like those observed in MRCF waveforms was observed, excepting for a response that often appeared in the occipital region as seen in panel d in Figure ​Figure1B.1B. This observation could be extended to those observed in the dipolar pattern of activation in the ipsilateral sensorimotor area, Inhibitors,research,lifescience,medical leading to a limitation for the number of dipoles specified in this area (Table ​(Table33). Table 3 The number of dipole source in brain areas of two hemispheres Discussion In this study, neural sources of MRCFs generated during a pulsatile extension of the index finger were modeled to ascertain whether multiple sharp components originate from independent source activities. Inhibitors,research,lifescience,medical Two to four sources (i.e., smf, sm1–sm3) were modeled independently across subjects. The position, orientation, and time-varying

patterns of these sources were compared to those obtained for the components in the SEF data. We found that all dipole sources for MRCFs were located in the same precentral region, oriented in the same Selleckchem KU-57788 direction in the cortical space, and exhibited the same time-varying wave profiles over the Carnitine palmitoyltransferase II movement time. These led us to suggest that there is no specific reason to deal with the four components of the MRCF waveform independently, but rather that all components of MRCF originate from the precentral motor area. Readiness field and MF Cortical activity preceding voluntary movements has been documented in neurophysiological studies in humans (Kornhuber and Deecke 1965; Barrett et al. 1986; Jahanshahi et al. 1995; Richter et al. 1997; Wildgruber et al. 1997) and monkeys (Gemba et al. 1980; Sasaki and Gemba 1981).