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Each action potential on the waveform selected by the "Spike W.F. #", in the range to be analysed, triggers a "sweep" from the waveform selected by the "Spike corr. W.F. #". The window and delay for these sweeps are set as they are for spike triggered averages. The sweep window is divided into a number of bins, which count the number of action potentials found in each part of every sweep analysed. The resulting graph shows the average number of action potentials in each part of the sweep window.
You can limit the number of spikes counted in each sweep, to a certain number allowed before the sweep was triggered (if using a negative delay), and a certain number allowed after the sweep was triggered. This is done by setting the parameters "Corr. spikes before trigger" and "Corr. spikes after trigger".
The program performs a test of statistical significance on the peak of the graph, and indicates above the graph if the peak is significant. A significant peak is one where the peak count exceeds the mean baseline count by more than 3.29 times the root of this mean. The results of a "K test" are also shown above the graph. These tests are described in "Short term synchronization of intercostal motoneurone activity" by T.A. Sears and D. Stagg, J. Physiol. (1976), 263, pp. 357-381.