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<p>Dear Fieldtrippers,</p>
<p>I was wondering whether you could provide some advice on the
optimal configuration for ft_artifact_zvalue function so that it
might more or less reliably detect electrode pop artifacts. When I
talk about electrode pops, I mean those artifacts with a very
sharp, high amplitude onset and a subsequent gradual decay. (We
use EEG, not MEG)<br>
</p>
<p>I have been trying the configuration for detecting SQUID jumps as
suggested on the corresponding tutorial page, but I realized SQUID
jumps look quite different than electrode pops, especially after
the initial sharp onset. <br>
</p>
<p>My approach is to use ft_artifact_zvalue to generate sample
markers for the artifacts, and then use ft_rejectartifact with the
preprocessed data loaded into the workspace to remove those
trials.</p>
<p>This has been my configuration so far:</p>
<p>% +++ Jump artifact config +++<br>
cfgJump = [];<br>
cfgJump.continuous = 'no';<br>
% channel selection, cutoff and padding<br>
cfgJump.artfctdef.zvalue.channel = target_chn;<br>
cfgJump.artfctdef.zvalue.cutoff = 60;<br>
cfgJump.artfctdef.zvalue.trlpadding = 0;<br>
cfgJump.artfctdef.zvalue.artpadding = 0;<br>
cfgJump.artfctdef.zvalue.fltpadding = 0;<br>
% algorithmic parameters<br>
cfgJump.artfctdef.zvalue.cumulative = 'yes';<br>
cfgJump.artfctdef.zvalue.medianfilter = 'yes';<br>
cfgJump.artfctdef.zvalue.medianfiltord = 9;<br>
cfgJump.artfctdef.zvalue.absdiff = 'yes';</p>
<p>I appreciate any help on this!</p>
<p>Cheers,<br>
Jan Ostrowski<br>
</p>
<p>
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<pre class="moz-signature" cols="72">--
Jan Ostrowski, M.Sc.
Department of Systems Neuroscience
University Medical Center Hamburg-Eppendorf
Martinistr. 52
Building W34, Room 320b
D-20246 Hamburg, Germany</pre>
<br><div><hr size="1" style="color: #999999;"><p style="color: #999999; font-size: x-small;">Universitätsklinikum Hamburg-Eppendorf; Körperschaft des öffentlichen Rechts; Gerichtsstand: Hamburg | <a href="http://www.uke.de/">www.uke.de</a><br>Vorstandsmitglieder:
Prof. Dr. Christian Gerloff (Vorsitzender), Joachim Prölß, Prof. Dr.
Blanche Schwappach-Pignataro, Matthias Waldmann (komm.)</p><hr size="1" style="color: #999999;"><p style="color: #999999; font-size: x-small;">SAVE PAPER - THINK BEFORE PRINTING</p></div></body>
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