Dear Chris and the MEG community,
I have just had my first experience with eye-tracking in both MEG and
fMRI experiments. Subjects performed saccades as responses to
two-alternative forced choices.
Here at the MEG Center in Tuebingen, we newly bought the MI01 Mono PC-60
integrator system ( PCI framegrabber and ViewPoint software only ) from
Arringtonreseach (http://www.arringtonresearch.com/headfixed.html).
In the fMRI study, I used the video output from the SMI set-up (IR
illumination and camera goggle) and fed the video information (60Hz)
into the ViewPoint software. Despite the interferences from the scanner
on the video signal, all saccades could be identified in post-processing.
In the MEG study, I used a digital camera with long-range optics (50Hz,
about 150 cm distance) that fed the video signal to the Software, which
worked perfectly. We mounted the two IR lamps (on each side) and the
camera on the armrest using a custom-made aluminum structure.
To set up the eye tracker for the MEG as well as the fMRI experiments,
it required me, a non-physicist, about 15 minutes usually. The data
analysis was performed offline using custom-written matlab scripts. So
far, I am very satisfied with the eye-tracking experience and the results.
Anyone who is interested in our eye-tracking set up is of course very
welcome to visit us at the MEG Center in Tuebingen.
Best regards,
Yiwen
---------------------------------------------------------------------------------
Yiwen Li Hegner, PhD
MEG-Center
Institute of Medical Psychology and Behavioral Neurobiology
University of Tübingen
Otfried-Müller-Str.47, 72076 Tübingen, Germany
Tel.: 0049-7071-29-87750
Fax : 0049-7071-29-5706
E-Mail: [log in to unmask]
Am 27.09.2010 14:44, schrieb Christopher Bailey:
> Dear Michael and others,
>
> Thank you for your comments and additional criteria to score systems by.
>
> I also have one further addition to the list: "usability". If anyone
> out there has user-level experience they would like to share with the
> rest of us, please don't hesitate to chime in! This could include
> matters like setup time/effort required per subject, ease-of-use of
> recording/analysis software, etc.
>
> "How many physicists does it take to run an eye-tracker?"
>
> /Chris
> --
> Christopher Bailey, MSc
> MEG Engineer, MINDLab Core Experimental Facility
> Center of Functionally Integrative Neuroscience (CFIN)
> Aarhus University, Denmark
>
> Postal address:
> B. 10G, DNC 5th floor, Norrebrogade 44
> Aarhus University Hospital, 8000 Aarhus C
> Denmark
>
> tel. cell: +45-2674-9927
> tel. office: +45-8949-9944
> fax office: +45-8949-4400
>
>
>
>
> On Mon, Sep 27, 2010 at 10:29 AM, Michael Wibral<[log in to unmask]> wrote:
>> Dear Chris,
>>
>> thank you very much for your initiative. I will be very glad to put up your summary on the website (note that it should be as objective as possible and stick closely to the facts). The problem with comparing eyetrackers in depth is that most sites only have one device.
>>
>> In my view you're correct about the sampling rate leaving only the SR Research device at the moment. As far as IR illumination is concerned I can also report, that you can spot the SR Research illuminator, when the lights in the MSR are dimmed low or off. However, from my experience with eyetrackers that seems to be always the case (SR Reserach and ASL long range products?).
>> Two things that you didn't mention in your list of criteria are:
>> (1) the level of residual artefacts in the MEG signals or, equivalently, the closest possible distance to the eye that you can reach without unacceptably large artefacts.
>> (2) Software and hardware interoperability with MEG devices (i.e. output to generic ADC channels of the MEG, compatibility of sampling rates (eyetracker/MEG) ) and stimulus presentation software.
>>
>> Since you're relatively close, you could also have a look at our installations in the MRI (ASL longrange, Resonance technology goggles) and MEG (SR Research) in Frankfurt.
>>
>> Michael Wibral
>> (Section Editor of the "Instrumentation - Peripherals" section)
>>
>>
>>
>>
>>
>>
>> -----Ursprüngliche Nachricht-----
>> Von: "Christopher Bailey"<[log in to unmask]>
>> Gesendet: Sep 24, 2010 5:44:59 PM
>> An: [log in to unmask]
>> Betreff: On MEG-compatible eye-trackers
>>
>>> Dear MEG Community,
>>>
>>> We are building an MEG-lab here in Aarhus, Denmark, and are in the
>>> process of sorting out our peripherals. There is not much in the
>>> "Instrumentation - Peripherals" -section on the website, so I would
>>> like to ask everyone out there with experience on eye-tracking in an
>>> MEG-setting the following questions. I will gladly take on the task of
>>> writing up a summary to be placed on the website for future reference!
>>>
>>> I would like to hear about the pros and cons associated with the
>>> MEG-compatible eye-tracking solutions currently on the market. I've
>>> been able to identify three vendors:
>>>
>>> 1) SMI (http://www.smivision.com/en/gaze-and-eye-tracking-systems/products/iview-x-mri-meg.html)
>>> 2) SR Research (http://www.sr-research.com/solutions_meg.html)
>>> 3) ASL (http://asleyetracking.com/site/Products/EYETRAC6Series/LongRangeOptic/tabid/69/Default.aspx)
>>>
>>> I do realise there are quite a few dimensions along which to compare
>>> these devices, but would appreciate any insight you may have. If
>>> sampling rate were the only deciding factor, there would surely be
>>> only one way to go (2). Another factor could be the light source
>>> ("pure" IR vs. "ups-there's-a-little-visible-light-too") illuminating
>>> the iris. We would also be keen on hearing if
>>> fMRI-compatibility/-usability has had anything to do with your choice
>>> of MEG eye-tracker.
>>>
>>> Btw: Our Elekta Neuromag-system will be installed in January 2011.
>>>
>>> Best regards,
>>>
>>> Chris
>>> --
>>> Christopher Bailey, MSc
>>> MEG Engineer, MINDLab Core Experimental Facility
>>> Center of Functionally Integrative Neuroscience (CFIN)
>>> Aarhus University, Denmark
>>>
>>> Postal address:
>>> B. 10G, DNC 5th floor, Norrebrogade 44
>>> Aarhus University Hospital, 8000 Aarhus C
>>> Denmark
>>>
>>> tel. cell: +45-2674-9927
>>> tel. office: +45-8949-9944
>>> fax office: +45-8949-4400
>
>
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