[FieldTrip] Source localizing auditory steady state responses

[McGowin, Inna]

Hey May,
Beamorming on correlated sources is my interest too. The problem is that
most beamformers (I deal with SAM and vector beamformer) are going to
suppress or/and misplace any correlated source. The way I deal with this
problem is by creating a region of interest (around primary auditory
cortex) and beaformer over each ROI separately.  The signal correlation
problem is still there but with a lesser extant (I think). Here is a great
article on this topic:
Beamformer reconstruction of correlated sources using a modified source
model
and
Modified Beamformers for Coherent Source Region Suppression

Also if I localize evoked responses I always prefer dipole fitting over
other methods, you could try the moving dipolar fitting method and have
your wave former from the dipole t-course.
Let me know how it will go for you.
Cheers,
Inna


Inna McGowin


On Wed, Mar 19, 2014 at 12:17 PM, Heng-Ru May Tan <
Heng-RuMay.Tan at glasgow.ac.uk> wrote:

>
> Hi All,
> I am trying to localize frequency specific ASSR but have not been
> successful in doing so with the 'mne' method in the ft_sourceanalysis.
> At the sensor-level the topo plots show clear bilateral generators.
>
> Is it possible to localize the bilateral sources using beamforming? And
> would I need to create a different forward model?
> Additionally, I would also like to retrieve the source signals and ideally
> comparing between 2 time periods within the same trial.
>
> I would appreciate if someone could advise or comment on how best to go
> about doing so.
>
> Thanks,
> May
>
>
> --
>
>
> ____________________________________________________________________________________________________________________________________
>
> Heng-Ru *May* Tan, PhD.
>
>
> Institute of Neuroscience and Psychology (INP) ▫ Centre for Cognitive
> Neuroimaging (CCNi) ▫ College of Medical, Veterinary and Life Sciences
>
> University of Glasgow ▫ 58 Hillhead Street, Glasgow G12 8QB ▫ +44
> (0)141-330-5090 ▫ Heng-RuMay.Tan at glasgow.ac.uk
>
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