Paired whole-cell recordings from a layer VI–layer VI neuron pair (A), a layer VI–VP neuron pair (B), a layer VI–RTN neuron pair (C), a VP–VP neuron pair (D), an RTN–RTN neuron pair (E), and a VP–RTN neuron pair (F) reveal that prolonged bursts are synchronized in layer VI, VP, and RTN. Schematic drawings illustrate the location of the paired recordings in each experiment.