Page 1 of 1

How to extract ERPs for each individual letter from a .dat file

Posted: 21 Jan 2020, 16:51
by sophie
Hello all,

The task was a calibration phase of P300 speller with the checkerboard paradigm.The .dat file was generated from copy-spelling 5 letters in a run. How to segment this file into 5 files so that each contains data for one letter selection? Could someone please point me in right direction?
Thank you!

Re: How to extract ERPs for each individual letter from a .dat file

Posted: 22 Jan 2020, 10:12
by mellinger
Hi Sophie,

the PhaseInSequence state variable contains information about stimulus sequences:
https://www.bci2000.org/mediawiki/index ... InSequence
All stimulus presentations that are part of a letter selection count as a single stimulus sequence.
So you may cut your file where PhaseInSequence becomes 1.

HTH,
Jürgen

Re: How to extract ERPs for each individual letter from a .dat file

Posted: 28 Jan 2020, 20:38
by sophie
Thank you so much Jürgen! That is very helpful!