[Eeglablist] EEGLab trouble re-referencing my data to multiple electrodes

[Maria Coelho]

Hi,

Firstly, thank you for the open discussion list on EEGLab matters. I am
currently preprocessing my data and mailing lists like these are very
useful.

I am having difficulties in re-referencing my data.

By default in Brain Vision Recorder, my reference channel is Fp1. When I
import my .vhdr files to EEGLab interface, this channel doesn't appear in
"Edit --> Channel Locations" (as I am assuming EEGlab also refers to Fp1 as
my reference channel).

However, I have two references, in both earlobes: Fp1 and AF8, and I need
to reference my data to the mean of these two channels' data.

I have checked the procedure in EEGlab Tutorial, where I can create a new
channel (in Edit --> Channel Locations) in case the original reference does
not appear visible, as it is the case, in Fp1 for instance. Yet, by
creating Fp1 as a new channel and set it as my reference (as described in
Tutorials --> Preprocess Data --> Re-referencing --> Retaining the
reference channel), the new channel Fp1 does not contain its original data.

With this issue, I cannot proceed to the next step, where it is described
how to use two references as I wish to use (in Tutorials --> Preprocess
Data --> Re-referencing --> Re-referencing to multiple electrodes).

I am using the brain products 64-channel EEG system.

Thank you in advance, and I hope I was clear in describing my problem.
I look forward to hearing from you.

Maria Coelho