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P300 calibration session problem

Posted: 30 Nov 2012, 07:03
by mattspe
Hi,
I'm trying to perform a calibration session with p300 speller, following this tutorial:
http://www.bci2000.org/wiki/index.php/U ... on_Session
but I've a problem. The application doesn't change the target letter in the attended word. In my case the word is "THE" and the application loop on the set of the "T" letter.
Any suggestions?
Regards
Matteo

Re: P300 calibration session problem

Posted: 30 Nov 2012, 07:45
by gschalk
Do you see a matrix? Do you see flashing rows/columns? Do you see the EEG display? Does it seem to update properly?

Gerv

Re: P300 calibration session problem

Posted: 30 Nov 2012, 08:21
by mattspe
Hi,
yes, I see the p300 matrix flashing in according with parameters I've setted. I also see the eeg activity, shown correctly and, above the window, the word I've written in the "text to spell" form. But it didn't change from "THE (T)". The letter between bracet is the target letter, right? During the variuos sequences it doesn't change in "H".
Thank you for any suggestions.
Matteo

Re: P300 calibration session problem

Posted: 30 Nov 2012, 09:18
by gschalk
What is the value of the NumSequences parameter?

Gerv

Re: P300 calibration session problem

Posted: 30 Nov 2012, 09:21
by mattspe
15

Re: P300 calibration session problem

Posted: 30 Nov 2012, 21:56
by gschalk
It should change to the H after about 30-60secs or so. Did you wait that long?

Gerv

Re: P300 calibration session problem

Posted: 01 Dec 2012, 01:59
by mattspe
yes, I've waited for several minutes.

Re: P300 calibration session problem

Posted: 01 Dec 2012, 19:53
by gschalk
OK. Can you download the latest version of BCI2000 and try this with the stock installation, i.e., without any changes to the parameter files that come with the system? We should be able to establish that this works, and then we can fool with the parameters until it stops working. I have personally never seen the behavior that you describe.

Gerv

Re: P300 calibration session problem

Posted: 03 Dec 2012, 04:18
by mattspe
Hi!
Thank you for your help. I've just installed again the BCI2000(the version with contribution).
I'm using the emotiv epoc headset.
The only changes I've made from default parameters are:
- channel names
- sourceChGain to 1 for any channel
- highpass filter to 0.1 hz
It's because the system force to do this to start with application.
Now i've the eeg plot working on the screen, the p300 matrix window and the Erp window.
What I need to do to perform a calibration session?
Matteo

Re: P300 calibration session problem

Posted: 03 Dec 2012, 08:06
by gschalk
The calibration session is described in the P300 tutorials on doc.bci2000.org.

My question is whether you get the advancing of the characters now? If not, how about using the SignalGenerator batch/parameter files?

Gerv

Re: P300 calibration session problem

Posted: 05 Dec 2012, 05:11
by mattspe
Now the target letter changing seems to work.
I don't know why.