<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Dear Matthias, <div class=""><br class=""></div><div class="">I don’t know where your artifacts come from, but I have some suggestions that might help you getting close to the source.</div><div class="">- is it transient or do you find it throughout the whole recording?</div><div class="">- do you find it in more than one recording?</div><div class="">- does your choice of reference or filtering influence it?</div><div class=""><br class=""></div><div class="">Not sure it will lead to something, but at least you will have a better understanding of this artifact.</div><div class=""><br class=""></div><div class="">Best Anne</div><div class=""><br class=""></div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">Am 28.11.2018 um 15:15 schrieb Matthias Möller <<a href="mailto:MatthiasCMoeller@gmx.de" class="">MatthiasCMoeller@gmx.de</a>>:</div><br class="Apple-interchange-newline"><div class=""><div class=""><div style="font-family: Verdana;font-size: 12.0px;" class=""><div class="">Dear all, </div>
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<div class="">my name is Matthias and I am relatively new to the field of EEG analysis. I'm currently carrying out a study on the effects of natural sounds on the quantitative EEG in patients with Parkinson's disease at the universities of Vanvouver and Marburg. </div>
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<div class="">Right now I'm experiencing these weird artifacts as seen in the screenshot. It's sharp spikes, looking similar to ECG artifacts, but in frequencies of 7-12Hz. </div>
<div class="">They are also showing up in the independent components after ICA as well. </div>
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<div class="">The recording was done at a sampling rate of 500 Hz, I've applied a Band-Pass filter from 1-249Hz and two notch filters, 60 and 120 Hz (recording took place in Canada). </div>
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<div class="">Has anyone seem similar artifacts before and maybe even knows how to get rid of them?</div>
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<div class="">Many thanks in advance and all the best,</div>
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<div class="">Matthias</div></div></div><span id="cid:F60729E6-B91F-4A38-8C22-6ACD8D4737FD@wlan.sbg.ac.at"><9 Hz Artefact.JPG></span>_______________________________________________<br class="">fieldtrip mailing list<br class=""><a href="https://mailman.science.ru.nl/mailman/listinfo/fieldtrip" class="">https://mailman.science.ru.nl/mailman/listinfo/fieldtrip</a><br class="">https://doi.org/10.1371/journal.pcbi.1002202<br class=""></div></blockquote></div><br class=""></div></body></html>