Missing unit of Global Field Power

Hello,

I have used the Cluster function for Power to generate the global field power of 59 EEG electrodes, but when I view the results (image below), there is no unit, only scale. Is the base unit µV or V, or something else?

Hi @RenataKoch,

The units for the Power cluster function will be [V²] for EEG, and [T²] for MEG.

Being x of the shape [nSensors, nSamples], the Power function returns the average across sensors of the square of the all the signals: mean(x.^2, 1)

GFP is computed as the standard deviation across sensors: std(x, 1, 1)

The results between power function and GFS are very similar or event identical as the mean of all the sensor values at a given time point is zero most of the time. If average reference is used, power and GFP are the same.

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