Remove muscle artifacts using ICA

Wed Nov 3 17:41:23 CET 2010

and, you might also take a look at makeig's new paper on using ica to remove
artifact from EEG acquired while participants walked on a treadmill,

http://www.frontiersin.org/Human_Neuroscience/10.3389/fnhum.2010.00202/abstract

hth,
alex

On Wed, Nov 3, 2010 at 8:42 AM, Alexander J. Shackman <shackman at wisc.edu>wrote:

> re: ica
>
> you might also take a look at,
>
>
> http://psyphz.psych.wisc.edu/%7Eshackman/mcmenamin_shackman_davidson_ni2010.pdf
>
> in particular, the supplement appended to the end.
>
> good luck,
> alex
>
>
> On Wed, Nov 3, 2010 at 4:09 AM, Maarten De Vos <
> maarten.de.vos at uni-oldenburg.de> wrote:
>
>> Dear Marc,
>>
>> sometimes ICA is suboptimal for muscle artifacts.  Not always, depends
>> indeed how your data look like.
>>
>> for an alternative method, please see
>>
>> De Clercq W., Vergult A., Vanrumste B., Van Paesschen W., Van Huffel S.,
>> "Canonical Correlation Analysis Applied to Remove Muscle Artifacts From the
>> Electroencephalogram", IEEE Transactions on Biomedical Engineering, Vol.
>>  53, No. 12, December 2006, pp. 2583-2587.
>>
>> and De Vos M, Riès S, Vanderperren K, Vanrumste B, Alario FX, Van Huffel
>> S, Burle B.
>> Neuroinformatics. 2010 Jun;8(2):135-50.
>> Removal of muscle artifacts from EEG recordings of spoken language
>> production.
>>
>>
>> Hope this helps,
>> maarten
>>
>> jan-mathijs schoffelen wrote:
>>
>>> Dear Marc,
>>>
>>> Your figures seem to be missing, so it is hard to judge what the
>>> artifacts look like exactly. Could it be that one of your head localization
>>> coils was switched on througout the measurement?
>>> In general, if your goal is to do source localization, I would not try to
>>> fix ugly channels, but just omit them from the sensor-array, because there
>>> will be plenty of sensors left.
>>> The fixing operation (whatever way it is done, e.g. nearest neighbour
>>> interpolation, ICA etc) involves replacing each channel's estimate by a
>>> linear combination of a subset of/all other channels. You have to keep in
>>> mind that the solution to the forward model (i.e. the leadfields for the
>>> sources you want to estimate) have to take the same linear operation into
>>> account in order to give correct results. As such, irrespective of the fact
>>> that the noisy channels are on the edge of the array, interpolation does not
>>> really make sense, because you are not really improving the quality of your
>>> total signal array. Also, in this case, I don't expect that rejecting the
>>> independent component capturing the artifact will be that beneficial,
>>> because most likely the spatial topography of this component of this
>>> component will be confined to the three bad guys, with more or less random
>>> loadings on the rest of the channels. Did you check whether the artifact is
>>> present at the level of the reference sensors? If that's the case, you could
>>> consider applying the cfw and afw (compute fixed weights, and apply fixed
>>> weights) utilities from the 4D software.
>>> Best wishes
>>>
>>> Jan-Mathijs
>>>
>>>
>>> On Oct 28, 2010, at 7:11 PM, Marc Recasens wrote:
>>>
>>>  Dear all,
>>>>
>>>> I have quite a naive question.
>>>> I'm processing some MEG (4-D) datasets in order to use source location
>>>> methods afterwards. One of my concerns is that I have some channels (3 in a
>>>> row) with a steady high frequency artifact >50Hz (I thought it is muscle
>>>> activity, However it is very tonic and present during the whole recording)
>>>> which is within my frequencies of interest. This can be seen in the attached
>>>> figures: timelocked responses bandpass filtered between 15 and 150 Hz, and
>>>> time-frequency activity between 50 and 100 Hz.
>>>> As the artefactual channels are put altogether in the right edge of the
>>>> sensor array (A148, A147 and A146) interpolation may not be a suitable
>>>> method to eliminate those artefactual channels. (?)
>>>>
>>>> I was wondering whether it is possible to correct those artifacts using
>>>> ICA in such a way similar to ECG artifact removal using component analysis,
>>>> that is, by identifying  and remove those components in the source analysis
>>>> that explain the high-frequency artifacts present in some of my channels.
>>>>
>>>> Thanks a lot.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Marc Recasens
>>>> Tel.: +34 639 24 15 98
>>>>
>>>> ---------------------------------------------------------------------------
>>>> You are receiving this message because you are subscribed to
>>>> the FieldTrip list. The aim of this list is to facilitate the discussion
>>>> between users of the FieldTrip toolbox, to share experiences
>>>> and to discuss new ideas for MEG and EEG analysis.
>>>> See also http://listserv.surfnet.nl/archives/fieldtrip.html
>>>> and http://www.ru.nl/neuroimaging/fieldtrip.
>>>>
>>>> ---------------------------------------------------------------------------
>>>>
>>>>
>>> Dr. J.M. (Jan-Mathijs) Schoffelen Donders Institute for Brain, Cognition
>>> and Behaviour, Centre for Cognitive Neuroimaging,
>>> Radboud University Nijmegen, The Netherlands
>>> J.Schoffelen at donders.ru.nl <mailto:J.Schoffelen at donders.ru.nl>
>>> Telephone: 0031-24-3614793
>>>
>>> ---------------------------------------------------------------------------
>>> You are receiving this message because you are subscribed to
>>> the FieldTrip list. The aim of this list is to facilitate the discussion
>>> between users of the FieldTrip toolbox, to share experiences
>>> and to discuss new ideas for MEG and EEG analysis.
>>> See also http://listserv.surfnet.nl/archives/fieldtrip.html
>>> and http://www.ru.nl/neuroimaging/fieldtrip.
>>>
>>> ---------------------------------------------------------------------------
>>>
>>>
>>
>> ---------------------------------------------------------------------------
>> You are receiving this message because you are subscribed to
>> the  FieldTrip list. The aim of this list is to facilitate the discussion
>> between  users of the FieldTrip  toolbox, to share experiences
>> and to discuss  new ideas for MEG and EEG analysis.
>> See also http://listserv.surfnet.nl/archives/fieldtrip.html
>> and http://www.ru.nl/neuroimaging/fieldtrip.
>>
>> ---------------------------------------------------------------------------
>>
>
>
>
> --
> Alexander J. Shackman, Ph.D.
> Wisconsin Psychiatric Institute & Clinics and
> Department of Psychology
> University of Wisconsin-Madison
> 1202 West Johnson Street
> Madison, Wisconsin 53706
>
> Telephone: +1 (608) 358-5025
> Fax: +1 (608) 265-2875
> Email: shackman at wisc.edu
> http://psyphz.psych.wisc.edu/~shackman<http://psyphz.psych.wisc.edu/%7Eshackman>
>

-- 
Alexander J. Shackman, Ph.D.
Wisconsin Psychiatric Institute & Clinics and
Department of Psychology
University of Wisconsin-Madison
1202 West Johnson Street
Madison, Wisconsin 53706

Telephone: +1 (608) 358-5025
Fax: +1 (608) 265-2875
Email: shackman at wisc.edu
http://psyphz.psych.wisc.edu/~shackman

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You are receiving this message because you are subscribed to
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and to discuss  new ideas for MEG and EEG analysis.
See also http://listserv.surfnet.nl/archives/fieldtrip.html
and http://www.ru.nl/neuroimaging/fieldtrip.
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