Slide 10

The frequency of chattering is dependent upon the intensity of current injection

Intracellular injection of depolarizing current pulses results in repetitive burst firing in chattering cells, the frequency of which is dependent upon the intensity of current injection (A,B, D). Each burst of action potentials consists of a single spike followed by a fast afterhyperpolarization, followed by a short after depolarization that may or may not initiate additional action potentials (C). In between bursts of spikes are hyperpolarizations that determine the interburst interval.
From Gray, C.M. and McCormick, D.A. Chattering cells: superficial pyramidal neurons contributing to the generation of synchronous oscillations in the visual cortex. Science 274: 109-113.