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'single stimulus P3' information and statistics

Posted: 13 Mar 2012, 10:59
by paolobernardis
Dear All,

we are working with the P300 spelling application..as far as I know, each time I create a plot using the "Offline analysis tool", I obtain two lines (correct/uncorrect) representing the mean response (within the data I am analysing) elicited by expected\unexpected stimuli. So, the lines represent the mean P300response among all the flashes and sequences..I was wondering if it is possible to have information about the response evoked by the single stimulus, and\or caclulate some statistics (i.e. std, median...)of the given P300 mean.

Thank you so much,

kind regards.

Re: 'single stimulus P3' information and statistics

Posted: 15 Mar 2012, 21:51
by boulay
Hi,
This is fairly trivial to do by yourself if you have access to and are familiar with MATLAB (Octave should work too). Doing it in such a way will also allow you to calculate whichever statistics you like, whether it be sample-time-by-sample-time or on the peak-to-peak amplitude, or the RMS, or any arbitrary measure. It will also allow you to use the data for other things more easily.

This explains how to load the files into Matlab:
http://www.bci2000.org/wiki/index.php/U ... _MEX_Files

From there it isn't too difficult to extract the ERPs. I am happy to help you get started if you think this is something you want to do.

(Is there a way to move this topic to a more appropriate sub-forum?)

Re: 'single stimulus P3' information and statistics

Posted: 16 Mar 2012, 10:15
by mellinger
(Is there a way to move this topic to a more appropriate sub-forum?)
Thanks for your suggestion, I created a new "Data Analysis" subforum, and moved respective posts there.

Regards,
Juergen