<div>Hello,</div> <div>I have a question on the baseline setting of ERSP.</div> <div> </div> <div>I want to use the eeg before stimulus onset (from a timepoint before the stimulus to the stimulus onset) as the baseline and to compute the ERSP related to the response.</div> <div> </div> <div>The continuous eeg data was epoched according the stimulus and response.</div> <div> </div> <div>When the epochs relative to the response were longer than the epochs relative to the stilmulus, the powbase from the stimulus-epoch can not used as the baseline of the response-epoch, for the matrix is not consisten.</div> <div> </div> <div>But I do not use a very long stimulus-epoch, for example, as long as 1500ms or longer than that. </div> <div> </div> <div>Could I segment the stimulus-epoch to be a little longer, such as from a timepoint before the stimulus to a timepoint after the stimulus onset, may be </div> <div>-1000~500ms, and
compute the powbase. If the response-epochs are -1200~300ms(response onset as zero), then use the powbase matrix from the stimulus-epochs as the baseline to compute the ERSP, the matrix will be consistent.</div> <div> </div> <div>I do not know whether this is correct, so I am look for your suggestions.</div> <div> </div> <div>Lili Wu</div> <div> </div> <div> </div> <div> </div> <div> </div><p>
<hr size=1><a href="http://cn.mail.yahoo.com/" target=blank>
ÑÅ»¢Ãâ·ÑÓÊÏä3.5GÈÝÁ¿£¬20M¸½¼þ£¡</a>