Bursts evoked in non-GABAergic neurons in the SGS and SO. A1, B1, Under control conditions, SGS stimulation evoked single action potentials in both SGS (A1) and SO (B1) non-GABAergic neurons. Insets, Voltage responses of these neurons to various current pulses. The bottom traces indicate the injected currents. A2, B2, In the presence of gabazine (10 μm), SGS stimulation evoked bursts in both neurons. A3, B3, Addition of CGP (3 μm) greatly increased the duration of bursts.