The EMG (electromyography) signals were recorded with a bandpass filter of 0.1–100 Hz online at a sampling rate of 600 Hz. MEG recordings The MEG signals were recorded as described elsewhere (e.g., Wasaka and Kakigi 2012), with a helmet-shaped 306-channel detector array (Vectorview; Eleka Neuromag Yo, Helsinki, Finland), which comprised 102 identical triple sensor elements. Each sensor element consisted of two orthogonal planar gradiometers and one magnetometer coupled

to a multi-SQUID (superconducting Inhibitors,research,lifescience,medical quantum interference device) and thus provided three independent measurements of the magnetic fields. The MEG signals were Inhibitors,research,lifescience,medical recorded at a 600 Hz sampling rate online with a bandpass filter of 0.1–300 Hz. Raw records for MEG, EMG signals, and trigger pulse signals were all stored continuously on the same computer for off-line analysis. Prior to the MEG recording, four head position indicator (HPI) coils were placed at specific sites on the scalp. To determine the exact location of the head with

respect to the MEG sensors, an electric current was fed to the HPI coil, and the resulting magnetic fields were measured with the MEG sensors. These procedures allowed for alignment of the individual head coordinate system with the MEG coordinate Inhibitors,research,lifescience,medical system. The location of the HPI coils with respect to the three anatomical landmarks (nasion and bilateral preauriculas) was also measured using Inhibitors,research,lifescience,medical a three-dimensional (3D) digitizer to align the coordinate systems of MEG with magnetic resonance (MR) images, obtained with a 3T MR selleck chemicals Tipifarnib imaging system (Allegra; Siemens, Erlangen, Germany). Analyses In the movement task, trials that generated artifacts due to corrective EMG activities before or during movement,

or trials that were initiated without an intertrial interval less than 5 sec, were removed following manual inspection on a trial-by-trial basis. Each data set of MEG Inhibitors,research,lifescience,medical and EMG signals was time locked to the trigger signal and averaged. The time window Brefeldin_A of the analysis was from 3000 msec before (−) to 3000 msec after (+) the onset of the trigger signal, and for MEG recordings the prestimulus period from −3000 to −2000 msec was used as the DC baseline. The number of trials used for the analysis averaged 86 (±5) across subjects. As recorded magnetic fields in each coil are a summation of those from temporally overlapping multiple source activities, a multiple source analysis method has been used to differentiate each source activity (Mauguière et al. 1997; Hari and Forss 1999; Inui et al. 2004; Wang et al. 2004; Jung et al. 2009). We adopt the modeling procedure implemented in BESA 5.