3 ± 6.9 msec before the onset of active movement. No statistical difference was observed in the electromechanical delay from the onset of EMG activity to the onset of movement between the MEG experiment conducted inside the shielded room and the preexperiment conducted outside the shielded room. Furthermore, as in the preexperiment conducted outside the shielded room, no EMG activity was observed in the extensor indicis muscle during PM in the MEG experiment. MEG signal amplitude (RSS) Figure 2 shows the whole-head click here distribution of

the RSS waveforms from a representative subject 500 msec before and 500 msec Inhibitors,research,lifescience,medical after movement onset following active and passive movements, with the enlarged RSS waveforms from two locations during active and passive finger extensions. In all subjects, the largest amplitudes for both active and passive movements were elicited from the same sensor at the sensorimotor area over the hemisphere contralateral to Inhibitors,research,lifescience,medical the movement. The small response over the hemisphere ipsilateral to the movement was elicited only by PM and only in some subjects. Figure 3 shows the superimposed RSS waveforms obtained from all subjects at the sensor of the greatest

response in each subject following active and passive movements. The large MEF1 response was elicited immediately after the onset of active movement in all subjects (Fig. 3A). In contrast, Inhibitors,research,lifescience,medical two peaks in the RSS waveform were clearly elicited immediately after the onset of PM (Fig. 3B) and Inhibitors,research,lifescience,medical were referred to as PM1 and PM2, respectively. The averaged RSS waveforms of all subjects following active and passive movements are shown in Figure 3C. Table 1 shows the latencies and amplitudes of the peak responses in all subjects. The peak latency of MEF1 was observed 35.3 ± 8.4 msec after the onset of movement and 84.6 ± 10.0 msec after the onset of EMG activity. The responses following PM over the hemisphere contralateral to the movement

peaked at 36.2 ± 8.2 msec in PM1 and 86.1 ± 12.1 msec in PM2 after movement onset. No Inhibitors,research,lifescience,medical significant difference was observed in latency between MEF1 and PM1. The peak amplitudes of these components were 138.6 Rolziracetam ± 43.4 fT/cm in MEF1, 111.4 ± 31.9 fT/cm in PM1, and 103.3 ± 35.1 fT/cm in PM2. In only six subjects, we clearly identified a small response over the hemisphere ipsilateral to the PM. This response peaked at 115.0 ± 29.9 msec, and the peak amplitude was 89.0 ± 31.0 fT/cm. Table 1 Peak latencies and amplitudes of RSS waveforms at the sensor showing the largest activation after active and passive movements in all subjects Figure 2 Whole-head distribution of the RSS waveforms from a representative subject following active and passive movements. Enlarged responses from the encircled channels are shown below. Channel (A) is located above the sensorimotor cortex contralateral to the …