[Eeglablist] Regarding Simultaneous fMRI-EEG Data

[Makoto Miyakoshi]

Dear Deepali,

The three steps you told me is the same.
Please check the following things:

1.Do you synchronize the MRI with the EEG recorder? Do you see 'sync on'
markers?
2.Do you use appropriate dynamic range and filter for recording signals?

Another thing which I believe important but not validated yet is the
placement of the EEG recorder. The following thing is not validated
officially, to please read it with caution. In the product manual, it is
recommended that you should sit it on the bore, but I found that EPI scan
shakes it terribly. You can easily confirm it by touching it while you run
EPI scan. Hold it in your hand in the air without touching the inner wall
and you still feels the vibration exactly in the same way. Believe it or
not, I had been falling the simultaneous recording more than 15 times, but
finally obtained good data just recently after removing the EEG recorder
out of the bore.

Makoto


--- Deepali Shewale <deepali.shewale at gmail.com> wrote:

>  Dear Makoto,
> Even i am working on similar stuff of removing Gradient and BKG
> artifact
> removal from EEG data in Analyzer. However, i am not able to remove
> the
> gradient artifact completely, there is still some residual artifact
> remaining in the data because of which it is not removing BKG
> artifact
> effectively also. I am removing gradient artifact in following way:
> 1] I am writing markers based on Volume.
> 2] Subtracting the template based on Correlation option.
> 3] Applying LPF using IIR filter. Slope for IIR filter 48 and
> cut-off Frequency 50 Hz.
> I feel i am doing all this step correctly following the manual, bt
> still not
> getting proper results. i am not getting where exactly i am going
> wrong. can
> you just help me out with this, if possible can you mail me the
> complete
> list of steps you are performing while doing Gradient artifact
> correction.
> 
> Thanks.
> > _______________________________________________
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to
> eeglablist-unsubscribe at sccn.ucsd.edu
> For digest mode, send an email with the subject "set digest mime" to
eeglablist-request at sccn.ucsd.edu