Figure 1
The simultaneous and synchronous presentation of the video-polygraph and sound signal of a myoclonic-atonic seizure associated with an initial vocalization (Case 3). The onset of the sound signal representing the ictal vocalization corresponded to that of myoclonic EMG potentials, which were immediately followed by an interruption of EMG activity associated with atonic falling. The onset of the sound signal also corresponded to the negative component of the spike-wave complex. The duration of the ictal vocalization was much longer than that of myoclonic EMG potentials. The video-polygraphic and sound-track windows were time-locked with a different time scale. Vertical bars (representing onset [solid line] and end [dashed line] of vocalization) in both video-polygraph and sound-track were time-locked.