Trial definition and artifact rejection

Christine Tillmann tillmann at MPIH-FRANKFURT.MPG.DE
Mon Aug 6 16:42:04 CEST 2007

Dear all,

I have a question concerning data preprocessing;
does anybody know how to specify different time windows
for 1) the definition of correct trials and 2) artifact rejection?

So far, I have used a function that looks for correct data segments
defined by a stimulus trigger and the button press following within a
1sec window after the trigger. These segments are then further analysed
with artifact rejection. Since I lose a lot of trials with this
procedure because reaction times seem to be a little longer, I wanna use
a longer time window, e.g. 2 sec., for defining correct trials, and then
shorten the segments again so that the artifact rejection and all
further analysis steps are only performed with 1sec. long windows....

I would be glad if anyone had an idea how to solve this problem!

Thanks in advance,

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