Figure 4. During fictive locomotion the V_th is hyperpolarized during both phases of the fictive step cycle.

In this extensor motoneurone, current pulses were delivered at approximately 1 Hz during fictive locomotion (lower traces show MLR-evoked ENG activity). One current pulse occurring during the inactive phase of the fictive step cycle elicited an action potential (marked by the arrow) with a V_th of -53.0 mV. This was the same as the V_th seen during the active phase, and was -3.0 mV hyperpolarized compared to control.