[Eeglablist] Epoching

[Bence Szaszkó]

Hi,

I currently investigate changes in brain activity depending on the 
modality people are currently attending.
There are two modalities in my dataset, visual and auditory.

I don't have trials, but continous 3 min blocks. I have distinct event 
codes when a block begins in the auditory (16) /visual modality (15), 
and when there is a switch between modalities (1)/(2). My first goal was 
to split up the dataset into 2 separate datasets, one for auditory, one 
for visual, which I managed to do. That means, I split up the data and 
put all the little auditory "chunks" together in one dataset, and visual 
in the other. Note that this not continuous data, and that each chunk 
can vary in length. There are also other event codes in the files, which 
can be ignored.

My next step would be to epoch the data. For the sake of simplicity, 
let's focus on visual chunks only. Epoching should start when there is 
an event 15 (begin of block) or an event 1 (switch to visual modality), 
setting 2 sec epochs until there is an event 2 (switch) or event 14 (end 
of block). Then, epoching should stop and start again at the next 1 or 
15.

Can I somehow achieve this in EEGLAB? Can anyone help me with this? :) I 
appreciate your effort.

Kind regards,
Bence

-- 
Bence Szaszkó, BSc MA MSc
University Assistant (prae doc)

University of Vienna
Faculty of Psychology
Department of Cognition, Emotion, and Methods in Psychology

Liebiggasse 5
A-1010 Wien/Vienna
Austria

e-mail: bence.szaszko at univie.ac.at