bci2000.org BBS

Hi

I am running a StimulusPresentation experiment and wanted to find out if there is a way to see after the experiment which Stimulus code the user was asked to focus on. I know this is specified in the parameter file, but is there a way to see this from the recorded data? So when I display it is there a state that can tell me when the user was asked to focus on what?
I would like to average the epochs in EEGLAB but I only want to average the epochs which have a P300 and at the moment I don't have a way of knowing which epochs to average based on which Stimulus the user had to focus on.

Thanks

Leandra

Leandra,

There is no state that defines this information. However, as you point out, all necessary information is stored in the datafile. What you could do is to load the data file into Matlab, reconstruct a "state" based on the information in the parameters, and save the resulting data using save_bcidat.

Gerv

As far as I understand your question, the information you ask for is contained in the StimulusType state. This state is set to 1 when the "attended stimulus" is being presented, and is 0 otherwise.

Juergen

Thank you for the replies.

The StimulusType parameter is exactly what I needed.

Thanks