Dear all,
Antoine, Etienne: this is indeed the default setup with neuromag which is clearly far from optimal – the transducers are actually placed further
away than the recommended spots. We are double-checking proper removal of those artifacts with sss for now (Antoine, I trust you have already been through that a lot so it sounds like good option for now) and optimal configurations in the short-term.
I am of course concerned by other points that have been raised, namely the sound quality that will be impacted with longer tubing etc. Some responses
provided offline are also quite telling and particularly relevant for speech studies and refined acoustics which we also plan to run here…
In sum, many thanks for the different recommendations from you all as we will likely look into a more sophisticated audio system in the very near
future. I might get back in touch with some of you for a better sense of the specifications you have opted for.
See you all in Biomag!
Best wishes,
Virginie
Virginie van Wassenhove . CEA.DSV.I2BM.NeuroSpin - INSERM Cognitive NeuroImaging Unit
Bât 145 Point Courrier 156 . Gif sur Yvette F-91191 . France
Ph: + 33 (0)1.69.08.1667 . [log in to unmask] . [log in to unmask]
http://sites.google.com/site/virginievanwassenhove
https://sites.google.com/site/ceaunicogmeg
From: Discussion list for international MEG community [mailto:[log in to unmask]]
On Behalf Of LABYT Etienne 226379
Sent: Friday, February 17, 2012 9:49 AM
To: [log in to unmask]
Subject: Re: [megcommunity] etymotic earphones and magnetometers
Dear Virginie,
Yes, indeed, this problem with Etymotic system is known and it is recommended to maintain with tape the transducers on the
small table in forn of the subject or better,, on the back of the MEG armchair (there are scratch to do this).
Bye
Etienne
Etienne Labyt, PhD
Responsable Imagerie
Responsable plateforme MEG/EEG
CEA-Leti, CLINATEC
MINATEC Campus, 17 rue des Martyrs
38054 GRENOBLE Cedex 9
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Tél. : + 33 (0)4 38 78 06 87 – Fax et/ou mobile : + 33 (0)4 38 78 53 55
www.leti.fr
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De : Discussion list for international MEG community [mailto:[log in to unmask]]
De la part de Antoine Ducorps
Envoyé : jeudi 16 février 2012 15:57
À : [log in to unmask]
Objet : Re: [megcommunity] etymotic earphones and magnetometers
Dear Virginie,
We also experienced this problem with our Elekta Triux, this was already the case with our previous CTF system.
As a solution, we keep the transducers as far as possible from the sensors, and for that longer audio tubes help (we had 1 meter tubes with CTF).
Then the remaining artefact should be well removed by SSS, as clearly originating from outside the sensor sphere.
Hoping this comment helps,
Antoine.
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CENIR - Centre de Magnétoencéphalographie
Tél (33) 1
42 16 11 62 (bureau)
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CENIR Plate-forme MEG-EEG
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Le 16 févr. 2012 à 15:31, VAN WASSENHOVE Virginie a écrit :
Dear all,
we noticed that some magnetometers could be sensitive to sounds sent through the Etymotic system - empty room/remotely from the system.
This appears to be directly due to the transducer parts.
Has any of you experienced such (very problematic) issue? Has attempts to better isolate this system been helpful?
Thanks in advance for any suggestion.
Cheers,
Virginie
Virginie van Wassenhove . CEA.DSV.I2BM.NeuroSpin - INSERM Cognitive NeuroImaging Unit
Bât 145 Point Courrier 156 . Gif sur Yvette F-91191 . France
Ph: + 33 (0)1.69.08.1667 . [log in to unmask] .
[log in to unmask]
http://sites.google.com/site/virginievanwassenhove
https://sites.google.com/site/ceaunicogmeg
