[FieldTrip] Spike artifacts 7-12Hz

Rodrigo Montefusco rmontefusco at med.uchile.cl
Thu Nov 29 22:31:40 CET 2018


Dear Matthias,

I use to have something like that. Have you noticed if that happened at
some particular time of the day? In my case it was solved after turning
some equipment off in a neighbor lab, or by doing the recordings early in
the morning, late in the night or during weekends.

Good luck!

Rodrigo

On Thu, Nov 29, 2018 at 5:56 PM Blume Christine <christine.blume at sbg.ac.at>
wrote:

> Dear Matthias,
>
>
> I would guess that if the ICA nicely removes this component that might be
> the best approach, it is also commonly used to remove eye blinks or ECG
> artefacts from data. You can also try to design your own filter if the
> artefact is really centered around 9 Hz,  although filtering is an issue on
> its own.
>
>
> Hope this helps!
>
> Christine
>
>
> ------------------------------
> *Von:* fieldtrip <fieldtrip-bounces at science.ru.nl> im Auftrag von
> "Matthias Möller" <MatthiasCMoeller at gmx.de>
> *Gesendet:* Donnerstag, 29. November 2018 16:55:26
> *An:* fieldtrip at science.ru.nl
> *Betreff:* Re: [FieldTrip] Spike artifacts 7-12Hz
>
> Dear all,
>
> thanks a lot for your prompt answers, that is really supportive, thank
> you!
>
>
> Testing is already done, so I can't test for devices anymore whether they
> produce artifacts or not.
>
> To be honest I'm running out of ideas which devices might have been
> responsible. I used bluetooth headphones where the frequency is a lot
> higher, and in some sets I don't have the artifacts although subjects were
> stimulated using the same headphones. It's not in all recordings but in
> some. If it's in the recording, then it is throughout the whole one.
> It's not influenced by referencing or filtering.
>
> Deep brain stimulation seems to be to high in frequency as well.
>
> For now the only thing I can do is to remove the respective components
> indeed.
> Does anyone else maybe have an idea about how to filter out/get rid of
> those artifacts?
>
> Best,
>
> Matthias
>
> *Gesendet:* Donnerstag, 29. November 2018 um 10:08 Uhr
> *Von:* fieldtrip-request at science.ru.nl
> *An:* fieldtrip at science.ru.nl
> *Betreff:* fieldtrip Digest, Vol 96, Issue 22
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> Today's Topics:
>
> 1. Re: Spike artifacts in EEG, 7-12Hz (Blume Christine)
> 2. Re: Spike artifacts in EEG, 7-12Hz (Marcin Koculak)
> 3. Re: Spike artifacts in EEG, 7-12Hz (anne Hauswald)
> 4. 15 PhD positions in Marie Slodowskwa-Curie Innovative
> Training Network “INFANS" (Uwe Graichen)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 28 Nov 2018 15:04:32 +0000
> From: Blume Christine <christine.blume at sbg.ac.at>
> To: "fieldtrip at science.ru.nl" <fieldtrip at science.ru.nl>
> Subject: Re: [FieldTrip] Spike artifacts in EEG, 7-12Hz
> Message-ID: <07979b73a31a4cb5bd02398211e36ec6 at sbg.ac.at>
> Content-Type: text/plain; charset="utf-8"
>
> Dear Matthias,
>
> Admittedly, I do not know what this could be. While the first step should
> of course be to find the source and eliminate this (any devices in the EEG
> lab, artefact from the acoustic stimulation/headphones, …), in case you are
> unable to find it, you could remove the component(s) that correspond to the
> artefact. But as I said, the first goal should always be to record clean
> data…
>
> Best,
> Christine
>
>
> Von: fieldtrip <fieldtrip-bounces at science.ru.nl> Im Auftrag von "Matthias
> Möller"
> Gesendet: Mittwoch, 28. November 2018 15:16
> An: fieldtrip at science.ru.nl
> Betreff: [FieldTrip] Spike artifacts in EEG, 7-12Hz
>
> Dear all,
>
> 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.
>
> 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.
> They are also showing up in the independent components after ICA as well.
>
> 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).
>
> Has anyone seem similar artifacts before and maybe even knows how to get
> rid of them?
>
> Many thanks in advance and all the best,
>
> Matthias
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>
> Message: 2
> Date: Thu, 29 Nov 2018 00:19:13 +0100
> From: Marcin Koculak <koculak.marcin at gmail.com>
> To: fieldtrip at science.ru.nl
> Subject: Re: [FieldTrip] Spike artifacts in EEG, 7-12Hz
> Message-ID:
> <CAJDQ6z46sUQacPVrWxWiNf8Hf25QeE=Hf4S92_kG--xnkdjjaQ at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> Dear Matthias,
> I have never seen such artifacts, but if you are working with patients with
> Parkinson's, have you checked if they have deep brain stimulation devices?
> Maybe that is causing the artifacts in the data?
> best,
> Marcin
>
> śr., 28 lis 2018 o 16:11 Blume Christine <christine.blume at sbg.ac.at>
> napisał(a):
>
> > Dear Matthias,
> >
> >
> >
> > Admittedly, I do not know what this could be. While the first step should
> > of course be to find the source and eliminate this (any devices in the
> EEG
> > lab, artefact from the acoustic stimulation/headphones, …), in case you
> are
> > unable to find it, you could remove the component(s) that correspond to
> the
> > artefact. But as I said, the first goal should always be to record clean
> > data…
> >
> >
> >
> > Best,
> >
> > Christine
> >
> >
> >
> >
> >
> > *Von:* fieldtrip <fieldtrip-bounces at science.ru.nl> *Im Auftrag von
> *"Matthias
> > Möller"
> > *Gesendet:* Mittwoch, 28. November 2018 15:16
> > *An:* fieldtrip at science.ru.nl
> > *Betreff:* [FieldTrip] Spike artifacts in EEG, 7-12Hz
> >
> >
> >
> > Dear all,
> >
> >
> >
> > 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.
> >
> >
> >
> > 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.
> >
> > They are also showing up in the independent components after ICA as well.
> >
> >
> >
> > 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).
> >
> >
> >
> > Has anyone seem similar artifacts before and maybe even knows how to get
> > rid of them?
> >
> >
> >
> > Many thanks in advance and all the best,
> >
> >
> >
> > Matthias
> > _______________________________________________
> > fieldtrip mailing list
> > https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
> > https://doi.org/10.1371/journal.pcbi.1002202
> >
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> ------------------------------
>
> Message: 3
> Date: Thu, 29 Nov 2018 09:26:20 +0100
> From: anne Hauswald <anne.hauswald at me.com>
> To: FieldTrip discussion list <fieldtrip at science.ru.nl>
> Subject: Re: [FieldTrip] Spike artifacts in EEG, 7-12Hz
> Message-ID: <CFB17262-B923-4234-AE1B-AD2BBDE6F50B at me.com>
> Content-Type: text/plain; charset="utf-8"
>
> Dear Matthias,
>
> I don’t know where your artifacts come from, but I have some suggestions
> that might help you getting close to the source.
> - is it transient or do you find it throughout the whole recording?
> - do you find it in more than one recording?
> - does your choice of reference or filtering influence it?
>
> Not sure it will lead to something, but at least you will have a better
> understanding of this artifact.
>
> Best Anne
>
>
> > Am 28.11.2018 um 15:15 schrieb Matthias Möller <MatthiasCMoeller at gmx.de
> >:
> >
> > Dear all,
> >
> > 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.
> >
> > 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.
> > They are also showing up in the independent components after ICA as well.
> >
> > 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).
> >
> > Has anyone seem similar artifacts before and maybe even knows how to get
> rid of them?
> >
> > Many thanks in advance and all the best,
> >
> > Matthias
> > <9 Hz Artefact.JPG>_______________________________________________
> > fieldtrip mailing list
> > https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
> > https://doi.org/10.1371/journal.pcbi.1002202
>
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> ------------------------------
>
> Message: 4
> Date: Thu, 29 Nov 2018 10:08:29 +0100
> From: Uwe Graichen <uwe.graichen at tu-ilmenau.de>
> To: fieldtrip at science.ru.nl
> Subject: [FieldTrip] 15 PhD positions in Marie Slodowskwa-Curie
> Innovative Training Network “INFANS"
> Message-ID: <fced2ce4-7d01-71bb-6134-1df7d0423293 at tu-ilmenau.de>
> Content-Type: text/plain; charset="utf-8"
>
> As part of the Marie Skłodowska-Curie Innovative Training Network
> “INFANS - INtegrating Functional Assessment measures for Neonatal
> Safeguard" http://www.infansproject.eu , funded by the European Union’s
> Horizon 2020 Research and Innovation Programme, we advertise 15 PhD
> positions.
>
> The goal of INFANS is to develop a new neonatal brain monitoring system,
> designed to overcome the severe shortage of clinically viable means to
> high quality monitor the brain function in infancy, crucial to prevent
> later life neurological, cognitive and motor impairment. To accomplish
> this goal, INFANS established a structured European PhD training
> programme in biomedical engineering, signal processing and clinical
> procedures to train a new generation of creative and entrepreneurial
> young researchers.
>
> The individual research projects of the early stage researchers (ESR)
> encompass the topics: technological innovation, industrial development,
> clinical validation, identification of neonatal healthcare needs. As
> part of their research the INFANS ESRs will develop a novel platform for
> high quality, clinically-viable EEG-NIRS monitoring accessible
> worldwide. Well-targeted visits and secondments, soft skills and dynamic
> training activities, an Open Science strategy, extensive involvement of
> ESRs in the network events organization, extensive contacts with other
> research, training and industrial European networks, dissemination
> activities and the award of Double doctoral degrees are further assets
> offered to INFANS ESRs.
>
> Excellent science, industrial leadership and societal challenge are
> merged in the INFANS network. The INFANS consortium includes 6 academic
> and 4 non-academic partners from 6 EU countries, among which leading
> universities, companies and clinical institutions. The partners involved
> in INFANS share complementary expertise and facilities to provide
> international, interdisciplinary and intersectoral research training and
> mobility that will complement local doctoral training. The INFANS ESRs
> will become independent researchers with improved career prospects in
> both the academic and non-academic sectors, and will advance the EU
> capacity for innovation in biomedical engineering.
>
> The institution and the place where the different ESR projects will be
> carried out, the scientific supervisor(s), individual research project
> titles, and contact person for each available position can be found
> specified in the attached document.
>
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