<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css" style="display:none"><!-- p { margin-top: 0px; margin-bottom: 0px; }--></style>
</head>
<body dir="ltr" style="font-size:12pt;color:#000000;background-color:#FFFFFF;font-family:Calibri,Arial,Helvetica,sans-serif;">
<p>Hi everyone</p>
<p> </p>
<p> </p>
<p>I have many trouble processing some data, due to the many bugs in the data. We don't know yet what causes them, maybe the cap is broken or some electrodes work bad, still to see.</p>
<p> </p>
<p> </p>
<p>Anyways, now here is what I do:</p>
<p> </p>
<p>- rereferencing</p>
<p>- filtering (0.5 - 50 Hz)</p>
<p>- Cutting the data into windows of 1 seconds. (They are not epochs; we don't have events informations).</p>
<p>- Removing the worst windows with some rejection criteria.</p>
<p>- Keeping the subjects where < 10% of the windows are removed.</p>
<p> </p>
<p>We I want to compute the statistics (ex, Fourier spectrum), I read that it was better not to re-concatenate the windows together since it could cause false frequencies. So I compute Fourier on each window and average their spectrum. However, smaller data
= less precise fourier spectrum. I am not really satisfied with the results. I feel that sometimes, the spectrum with a concatenated signal would be better. In particular, when I tried, I could see more alpha.</p>
<p> </p>
<p>What do you think?</p>
<p> </p>
<p> </p>
<p>P.S. I tried using ICA instead, but with only 8 channels (7 after re-referencing), it is very hard to do!</p>
<p> </p>
<p> </p>
</body>
</html>