Fig. 3.

Dependence of f–I relation characteristics on ramp current amplitude. A: the discharge pattern of a gastrocnemius-soleus (GS) motoneuron in response to a level of injected current that just exceeded threshold. Under these conditions, the MN displays an apparent type 3 response with a small negative ΔI (the difference between the currents at derecruitment and recruitment). B: the f–I relation for the same GS motoneuron in response to a higher level of injected current. Symbols and abbreviations are the same as those used in Fig. 1.