Saved data - Export function
Dear all,
during the last days i'm recording some basic eeg stuff.For instance one minute eyes open, eyes closed (for alpha blocking) and some random eye blinks. The aim of my recordings was just to see how i can export /save the data and then to see the waves/signal in EEGLAB (and Brainanalyzer)
At first i tried to save the data in EDF+ format. Wich is a standrad in EEG. In EEGlab however i just get high voltage peaks. It seems that there is not a real EEG signal saved in the EDF+ format. Does someone have experience with this? (i know that there is another thread about similar issues but not with this question).
Then i saved the data in CSV format, where the signal seems to have more sense. But i had to do some preprocessing staff to get the right channels to be displayed. For instance, when i'm importing the CSV into EEGlab there i get 16 channels, but the Ganglion only has 4. It seems that the time (hh/mm/ss) when i did the recording is also recognized as a channel in EEGLAB. After preprocessing i get the right channels and for the moment the correct data. I'm just wondering if someone has experience with that.
As well i wondered about the signal that is recorded. In the OpenBCI Gui the signals is in micro Volts rms (root mean square?), am I right? - Is there any possibility to change this into more standard output?
The FFT that is showed in the OpenBCI GUI, at a first moment, does not seems like a normal human FFT plot (hight voltage low frequencies and low voltage hight frequencies). I'm just wondering if this is normal.
For the moment i´m just guessing that i am recording real eeg signal. But just because i get clear EMG and Blink artifacs when i am causing it. I have experience with EEG but somehow it is difficult for me to interpret the GUI output.
Thanks for reading and for answering my questions.
Best,
Pascal.