Fig. 3.
Stimulation frequency, fstim, as a function of measured angular velocity [4]. The tanh function varies between 50–350 Hz with a baseline frequency of 200 Hz (zero angular head motion). A representative biphasic pulse is shown inside the graph. The amplitude and pulse duration (PD) of the cathodic pulse determine the charge delivered to the stimulation site. The PD and amplitude of the anodic pulse determine the charge returned from the tissue (balanced with input charge). The interphase gap (IPG) separates the two pulse periods and may be adjusted to optimize the neural response.