[Eeglablist] ERSP baseline

[Brian Roach]

EEGlab users,

I have what I hope is an easy question on the baseline period for ERSP data 
(in timef.m).  Let's say my epochs go from -1 to 2 seconds, and my window 
size for analysis is 128 samples.  If my AD rate is 1000Hz, and my baseline 
period is -1 to 0, will the last FFT that contributes to the average 
baseline power have the center of it 128 sample( or ms) window on 0, 
meaning data from 0-63ms contribute to the average, or does the baseline 
window center its last sample at -64 ms so that no data after the 0 point 
contribute to the baseline power?  On the other hand, does it continue even 
further than I think, and actually use an FFT from -1 to 127ms in 
calculating the baseline average as well?

I have been manipulating the "baseln" variable in the timef function for 
different baseline periods, but I would like to have a better idea of how 
those changes influence the ERSP data and plots.

Thank you,
Brian