Nerve-impulse patterns: a quantitative display technique for three neurons.

A scatter diagram is described that displays the relative timings of nerve impulses in 3 simultaneously monitored neurons. The technique is a generalization of the cross-correlation histogram for two impulse trains. The time intervals between impulses in different neurons are plotted on triangular coordinates to yield a Joint Impulse Configuration Scatter Diagram. The resulting 'snowflake' plot shows a pattern of spots and lines, which is interpretable in terms of the functional circuitry among teh neurons. Illustrations are given of the snowflakes produced by a variety of three-neuron circuits, which may serve as a preliminary catalog of snowflake types for interpretation of experimental data.