Fig. 2

Representative topographic map and MEP traces induced by single-pulse TMS recorded from the right ECR at ERD 35% and ERD 70%, calculated by the online FFT or LIA algorithm. A: Representative topographies of the averaged ERDs over trials during the resting condition (a), wrist kinesthetic motor imagery at ERD 35% (b) and ERD 70% (c) calculated by the online FFT algorithm, and ERD 35% (d) and ERD 70% (e) calculated by the online LIA algorithm, obtained from 128-channel EEG data. Topographic maps are illustrated in the most reactive frequency displaying motor imagery-related ERD. Data were obtained from Subject 9. Electrode positions are shown by dots. Negative values (blue colors) indicate strong ERD. B: Example MEP traces induced by single-pulse TMS recorded from the ECR during the resting condition (a) and during kinesthetic motor imagery of right wrist extension at ERD 35% (b) and ERD 70% (c) calculated by the online FFT algorithm, and ERD 35% (d) and ERD 70% (e) calculated by the online LIA algorithm. Thin gray lines represent representative MEP traces across 25 trials. Thick black lines represent the averaged MEP traces. The triangles and vertical lines represent stimulus onset (Stim). As ERD increased, MEP amplitudes induced by single-pulse TMS were facilitated in both cases of ERD estimations based on the online FFT and LIA algorithms. ECR, extensor carpi radialis; ERD, event-related desynchronization; FFT, fast Fourier transformation; LIA; lock-in amplifier; MEP, motor evoked potential; TMS; transcranial magnetic stimulation. Data were obtained from Subject 9