<div dir="ltr"><span style="font-family:arial,sans-serif;font-size:12.800000190734863px">Hi Lin,</span><div style="font-family:arial,sans-serif;font-size:12.800000190734863px"><br></div><div style="font-family:arial,sans-serif;font-size:12.800000190734863px">
That depends on what kind of <span class="">filters</span> you use, and how you remove your ocular artifacts. Obviously, if you are removing ocular artifacts by hand any <span class="">filtering</span> that will help you in detecting eye movements will be of course be of benefit. If you use a blind decomposition technique such as ICA to try and remove ocular artifacts, it's a bit more tricky. Some specific <span class="">filters</span> might help depending on what kind of other artifacts are present, but it's important for example not to smear out your eye movements. Before ones does ICA to remove artifacts it's a good idea to remove trials that are unfixable, like trials with jumps in them (i.e. hitting the ceiling of the amplifier). </div>
<div style="font-family:arial,sans-serif;font-size:12.800000190734863px"><br></div><div style="font-family:arial,sans-serif;font-size:12.800000190734863px">I can only help you further if you more precisely describe what you mean with <span class="">filtering</span> and ocular artifact removal. There are many many ways to go about these two.</div>
<div style="font-family:arial,sans-serif;font-size:12.800000190734863px"><br></div><div style="font-family:arial,sans-serif;font-size:12.800000190734863px">All the best,<br>Roemer</div></div><div class="gmail_extra"><br>
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<div class="gmail_quote">On Tue, Dec 18, 2012 at 11:00 AM, Roemer van der Meij <span dir="ltr"><<a href="mailto:r.vandermeij@donders.ru.nl" target="_blank">r.vandermeij@donders.ru.nl</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div dir="ltr">Hi Lin,<div><br></div><div>Could you provide a little more information? How did you reduce your ocular artifacts? How did you filter your data? What kind of fieldtrip settings did you use, and what fieldtrip version were you using? Adding a picture of the artifacts you're referring to might also help. </div>
<div><br></div><div>All the best,</div><div>Roemer</div><div class="gmail_extra"><br><br><div class="gmail_quote"><div><div class="h5">On Tue, Dec 18, 2012 at 2:55 AM, 蔡林 <span dir="ltr"><<a href="mailto:bertram0611@pku.edu.cn" target="_blank">bertram0611@pku.edu.cn</a>></span> wrote:<br>
</div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div class="h5">Hi all,<br>
<br>
Now I have an urgent problem about how to filter EEG data recorded in NeuroScan. I don't know the distiction between raw data(ie. cnt file)and the data after ocular artifact reduction. I filtered these two different data, and then I got diffrent results. Especially, I found many vertical lines after filtering the data through ocular artifact reduction, but I didn't find vertical lines filtering raw data.<br>
Please give me some advice about how to filter offset. Thank you in advance.<br>
<span><font color="#888888"><br>
--<br>
Lin Cai<br>
Department of Psychology, Peking University, Beijing 100871, P.R.China<br>
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Content preview: Hi all, Now I have an urgent problem about how to filter EEG<div class="im"><br>
data recorded in NeuroScan. I don't know the distiction between raw data(ie.<br>
cnt file)and the data after ocular artifact reduction. I filtered these two<br>
different data, and then I got diffrent results. Especially, I found many<br>
vertical lines after filtering the data through ocular artifact reduction,<br>
but I didn't find vertical lines filtering raw data. Please give me some<br></div>
advice about how to filter offset. Thank you in advance. [...]<br>
<br>
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<span class="HOEnZb"><font color="#888888"><br></font></span></div></div><span class="HOEnZb"><font color="#888888"><br clear="all"><div><br></div>-- <br><font size="3"><font color="darkblue"><font face="calibri">Roemer
van der Meij M.Sc.<br>
PhD Candidate<br>
Donders Institute for Brain, Cognition and Behaviour<br>
Centre for Cognition<br>
P.O. Box 9104<br>
6500 HE Nijmegen<br>
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E-mail: <a href="mailto:r.vandermeij@donders.ru.nl" target="_blank">r.vandermeij@donders.ru.nl</a></font></font></font><div style="line-height:130%;text-align:left;font-size:10px;overflow:hidden;margin-left:0px;word-wrap:break-word;margin-top:0px;padding:0px">
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</blockquote></div><br><br clear="all"><div><br></div>-- <br><font size="3"><font color="darkblue"><font face="calibri">Roemer
van der Meij M.Sc.<br>
PhD Candidate<br>
Donders Institute for Brain, Cognition and Behaviour<br>
Centre for Cognition<br>
P.O. Box 9104<br>
6500 HE Nijmegen<br>
The Netherlands<br>
Tel: +31(0)24 3655932<br>
E-mail: <a href="mailto:r.vandermeij@donders.ru.nl" target="_blank">r.vandermeij@donders.ru.nl</a></font></font></font><div style="padding:0px;margin-left:0px;margin-top:0px;overflow:hidden;word-wrap:break-word;color:black;font-size:10px;text-align:left;line-height:130%">
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