[Eeglablist] Importing data from Brain Vision Analyzer

[Katarzyna Dudzikowska]

Dear all,

I am about to embark on my very first EEG data analysis project. I received
data from my supervisor who works with Brain Vision Analyzer, I have .eeg,
.vmrk and .vhdr files. I understand that .eeg is the actual recording,
.vmrk contains information about the events and .vhdr is the metadata file
that I have successfully used to import the datasets into EEGLAB using
the bva-io plugin.

My problem is that I simply do not know whether the data I have includes
any preprocessing steps or not, or how I can tell. Would .eeg data in
principle be raw data? Or is it possible that it does already include some
artifact rejection and/or channel interpolation that has been performed on
this dataset in Brain Vision Analyser? Is there any way to figure it out
from the data itself? It imports as a single, continuous epoch.

Originally I was meant to work with already preprocessed data, but it seems
that I have to carry it out somewhat differently for my research goals. Can
I safely undertake my own preprocessing steps on the data as I have it?

I'd be very grateful for some help figuring this out.

Best,
Katia