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Dear Hatieng,
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<div>This might be the same issue we found when comparing eyes open to eyes shut. Take a look at this technical note to see how we addressed it:</div>
<div><a href="http://www.ncbi.nlm.nih.gov/pubmed/24412400">http://www.ncbi.nlm.nih.gov/pubmed/24412400</a></div>
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<div>Cheers, Mark.</div>
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<div>On 5 Jan 2015, at 14:23, Haiteng Jiang <<a href="mailto:haiteng.jiang@gmail.com">haiteng.jiang@gmail.com</a>> wrote:</div>
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<div dir="ltr">Hi all,
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<div> I performed DICS beamforming on resting-state data ( eyes closed) of a clinical population and controls. According to the sensor data, the control groups have more alpha-band (8-14
<div>Hz) activity over occipital areas after cluster statistic (attached figure upper plot) . Curiously, after beamforming , group comparisons showed the reversed patters in visual cortex (attached figure bottom plot) .Hence, the source-level results are
opposite to the sensor-level results. This is *not* a problem of the design matrix, or confusing the groups. I check the individual neural activity index on the single subject level . They make sense in general . I also tune the parameter a lot (tapper,
central frequency smooth frequency , regularization parameter , et al ), the opposite pattern remains. I understand that Beamformer images DO NOT DIRECTLY CORRESPOND TO ANY sensor data. However, the opposite pattern is really weird. I noticed that Tobias
Navarro Schröder had the similar issue 4 years ago (<a href="http://mailman.science.ru.nl/pipermail/fieldtrip/2011-May/003875.html">http://mailman.science.ru.nl/pipermail/fieldtrip/2011-May/003875.html</a>). Thus, I am not the only one who encountered this
problem.</div>
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<div> Any tips and suggestions will be greatly appreciated. Thanks in advance!</div>
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<div> Best,</div>
<div> Hatieng</div>
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-- <br>
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<div>Haiteng Jiang </div>
<div>PhD candidate</div>
<div>Donders Institute for Brain, Cognition and Behaviour</div>
<div>Neuronal Oscillations Group </div>
<div>Computational Cognitive Neuroscience Lab</div>
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<div><font face="arial, helvetica, sans-serif"><a href="https://sites.google.com/site/haitengjiang/" target="_blank">https://sites.google.com/site/haitengjiang/</a></font></div>
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<span><resting_issues.jpg></span>_______________________________________________<br>
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