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Analysis Help
Maintenance: Blanking


The blanking operation allows you to copy a waveform, blanking out certain sections that coincide with the occurrence of spikes on another waveform. The "Spike W.F. #" parameter, which is also used for action potential analyses, selects the latter waveform. You must also set the spike-related waveform parameters for this waveform.

You are presented a menu of parameters which you should set before proceeding. First, use the Number selection to set the waveform number for the data to be blanked. Use the Window selection to specify the length of the blanking interval triggered by each spike, and the Delay selection to specify the time (positive or negative) from the start of a spike to the start of the associated blanking interval.

Once these parameters, and the spike-related parameters mentioned above are all set, use the Go selection of this menu to begin the blanking operation. If the parameters have been set correctly, you are asked for the number of the new waveform, which must be different from the one being blanked, and different from the waveform used to trigger the blanking. If you enter the number of a waveform which already exists, this waveform is erased, and the new one takes its place.

A "sample and hold" technique is used to achieve blanking. I.e. the last sample in the waveform before the start of the blanking interval is repeated throughout the duration of the blanking interval, and the existing samples in that range are ignored.

If the "Blank averaged window" option is set, then instead of the sample and hold technique, the program will calculate the averaged sweep from all blanking intervals, and subtract this average from each interval. The idea is this average will represent a template of the artifact you want to remove from the signal.

 


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Copyright © 2017 G. R. Detillieux, Spinal Cord Research Centre, The University of Manitoba.