Figure 6. Subthreshold Membrane Potential Oscillations.
(A). Shows representative intracellular records of membrane potential for control (top: grey) and OX (bottom: red) motoneurons in response to matched depolarizing current injection. In record from OX motoneuron, dotted boxes outline prominent subthreshold oscillations and arrows point to hyperpolarization immediately preceding AP, designated pre-spike hyperpolarization. (B) Spike-triggered averages of membrane potential preceding all APs in current-matched trials control and OX motoneurons illustrating pre-spike hyperpolarization. (C) shows the observed (top) and predicted (middle) voltage slopes for the 15ms preceding AP threshold along with the average amplitude in pre-AP hyperpolarization (bottom).