Figure 2

Stimulation signals of HF DBS and pulsatile delayed feedback. The amplitude of the high-frequency pulse train of charge-balanced asymmetric biphasic pulses (solid lines) is (A) kept constant and equal to the parameter of the stimulation intensity K for HF DBS stimulation or (B) modulated by a slowly oscillating smooth feedback signal S(t) (8) for pulsatile LDF stimulation depicted by red dashed curves. The shapes of single pulses are schematically illustrated in the inserts, which can contain an interphase gap between the cathodic and anodic phases of the pulse.