Figure 1.

Direct demonstration of electrical coupling between two late-spiking interneurons by paired recording. A, Cartoon of the experimental configuration (top) and IR-DIC image of the pair in the living slice (bottom). B, Sequential injection of a depolarizing current step (150 pA) in cell₁ and cell₂ generates an attenuated response in the noninjected neuron. Insets show the attenuated responses at enhanced magnification; notice the presence of spikelets. V₁ and V₂ indicate the membrane potential recorded from cell₁ and cell₂, respectively, and I₁ and I₂ the current injected through the electrode. C and D illustrate the same experiment in a pair of interneurons with different firing patterns. Step injected, 100 pA.