Figure 3.

Definition of stimulation pattern and slow establishment of steady-state rebound delay. PY neurons were stimulated with rhythmic trains of hyperpolarizing pulses (downtime, hyperpolarization duration; uptime, duration without current injection; cycle period = downtime + uptime). Before stimulation, the neuron fired tonically. After stimulation began, the neuron initially did not fire (first two cycles) and then fired one, two, and finally three spikes, with continually decreasing rebound delay (cycles 3, 4, and 5).