Experiments in Movement Using DC-EEG, MEG, SPECT and FMRI

Abstract

Our volitional self-initiated acts are preceded by the Bereitschaftspotential (BP) or readiness potential [34,35]. The BP has an early component (BP1) and a late component (BP2, see Fig. 1). The early component BP1 lasts from the very beginning of the BP (1-2 s or more prior to movement onset depending on the complexity of the movement) to app. ½ s prior to movement onset and the late component BP2 lasts from ½ s before to the onset of movement itself (s 0 in Fig. 1). BP1 is symmetrical even for unilateral movement, while BP2 is larger over the contralateral hemisphere.