Author: Malcolm Lidierth

Updated: August 2008

Method

Phase correlation provides an estimate of the probabilty of observing an event as a function of the phase of a rhythm e.g. the step cycle. The trigger channel(s) provide the events that mark the start/stop times for the cycles. Results are returned as events/sweeps..

Options

Channel Selection

Select the trigger channels in the Channel A selector. These mark the onset of the rhythm to analyze. Note that only valid triggers will be used to mark the onset of each cycle but that all physical events will be scanned to find the end of the cycle. If the rhythm is interupted, set those events which mark the onset of each complete cycle as valid. Thus, if there are 10 cycles but the 10th is interupted, mark 1-9 as valid using the Channels menu in the sigTOOL data view.

Choose source channels using the Channel B selector.

Duration & Bin width

Sets the timebase for the resulting phase correlations and the bin width. The duration should be set in cycles and the binwidth in degrees.

Pre-time

Sets the pre-time as a percentage of the duration.

Sweeps per average

By default, all triggers will be used. To generate multiple correlations each with a fixed number of sweeps set Sweeps per Average to a number less than the total number of available triggers. The result will be presented as a 3-D histogram.

Post-processing options

Right-click the mouse on the plotted result to display a context-senstive menu. Menu options include the ability to superimpose a cumulative sum (cusum) plot and to add a smoothed plot of the data (smoothed with a Gaussian with a width of w bins).

© The Author and King's College London, 2008-