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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Dear FieldTrip users. </font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">I want to detect and remove EOG and ECG by using ICA. My data is from a Neuromag 306 MEG scanner with magnetometers and two orthogonal planar gradiometers. </font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">I assume that it is recommendable to do the ICA separately on each sensor type separately, i.e. on 1. magnetomers, 2. horizontal planar gradiometers, and then 3. vertical planar gradiometers, because they measure magnetic field changes at different scales and in different directions. </font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;"><b>Would you recommend to do ICA and other pre-processing steps separately on the horizontal and vertical planar gradiometers, or would you just combine the planar gradiometers with </b><i><b>ft_combineplanar</b></i><b> immediately? </b></font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">I'm worried that combining the two different gradiometer sensor types would violate underlying assumptions of the pre-processing algorithms, i.e. ICA, filters and baseline correction, because the planar gradiometer values are only positive valued estimates from the combinations of the original gradiometer measures, which do not seem to have oscillatory deflections around a baseline zero valued point. </font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Hope you can help. </font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Greetings</font></div>

<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Niels.</font></div>

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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Niels Trusbak Haumann</font></div>

<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">M.A. / PhD student</font></div>

<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Department of Aesthetic Studies / Center of Functionally Integrative Neuroscience</font></div>

<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Aarhus University / Aarhus University Hospital</font></div>

<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">E-mail: <a href="mailto:aestnth@hum.au.dk">aestnth@hum.au.dk</a></font></div>

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