A phase-equation model for a large phase lead in manual tracking caused by intermittent visual information

We propose a phase-equation model for a large phase lead in manual tracking with intermittent visual information. We have recently reported that hand motion largely led to the target motion when the target was intermittently displayed with a specific timing (Takachi and Sawada, 2004). To adapt the general tracking model to the intermittent manual tracking, we suppose that the geometric factor coupling with the target velocity is indispensable as a feedforward control, and the feedback control intermittently contributes to the hand motion. Results of simulations show that the large phase lead is due to both the decrease in visual information and the synchronicity between the timing of target display and the effect of the rhythmic hand motion caused by the geometric property of the target path.