Figure 5. Voltage-dependent bursting properties in Dbx1⁺ and Dbx1⁻ neurons.

A, a Dbx1⁺ neuron showing inspiratory bursts at a baseline membrane potential of −62 mV (left), ectopic voltage-dependent bursts at a more depolarized membrane potential of −52 mV (centre) and in low-Ca²⁺ conditions (right). I_a refers to applied current to demonstrate that bursting is intrinsic after the network activity stops (i.e. no XII output). B, inspiratory bursts and XII output in a Dbx1⁻ neuron (left) and ectopic voltage-dependent bursts at more depolarized membrane potential (right). C, percentage of neurons with voltage-dependent bursting properties in a sample size of 91 Dbx1⁺ and 42 Dbx1⁻ neurons in the preBötC. Voltage (20 mV) and time (1 s) scale bars apply to all traces.