Figure 2.

Examples of firing modes observed in corticothalamic neurons. (A) Layer 5 low-threshold bursting neuron, demonstrating a burst of fast action potentials riding a slow depolarizing wave at stimulus onset. (B) A small number (7/34) of layer 5 low-threshold bursting cells showed repetitive bursting at low threshold. (C) Regular spiking layer 5 corticothalamic neuron. (D) Example of a high-threshold bursting neuron. In this case, the neuron fires a train of individual action potentials in response to a 200 pA current step and then fires a burst of action potentials in response to a 250 pA current step. (E) Example of a layer 6 corticothalamic neuron. This neuron fires a train of individual action potentials in response to a depolarizing pulse. Action potential heights are truncated for clarity.