The spike-triggered averaging
(STA) is a tool for characterizing the response properties of a neuron using the spikes emitted in response to a time-varying stimulus. The STA provides an estimate of a neuron's linear receptive field. It is a useful technique for the analysis of electrophysiological data.
Mathematically, the STA is the average stimulus preceding a spike.[1][2][3][4] To compute the STA, the stimulus in the time window preceding each spike is extracted, and the resulting (spike-triggered) stimuli are averaged (see diagram). The STA provides an unbiased estimate of a neuron's receptive field only if the stimulus distribution is spherically symmetric (e.g., Gaussian white noise).[3][5][6]
^Lee and Schetzen (1965). Measurement of the Wiener kernels of a non- linear system by cross-correlation. International Journal of Control, First Series, 2:237-254