[FieldTrip] reconstructing EEG using leadfield (Beamformer)

[Tyler Grummett]

Thank you clearing that up eelke :)

Tyler

Sent from my iPhone

> On 20 Aug 2014, at 10:03 pm, "Eelke Spaak" <eelke.spaak at donders.ru.nl> wrote:
> 
> Hi Tyler,
> 
> Beamforming is a scanning method, which means that the power/current
> density at each grid point is estimated independently from all other
> grid points. In general one would not expect sum_i(leadfield_ix *
> pow_i), where i indexes grid points, to faithfully reproduce the
> potential measured at sensor x. This as opposed to something like e.g.
> minimum-norm estimate, where the estimation is done in one
> regression-like step, rather than by scanning grid points.
> 
> Best,
> Eelke
> 
>> On 20 August 2014 04:47, Tyler Grummett <tyler.grummett at flinders.edu.au> wrote:
>> Hello fieldtrip experts,
>> 
>> I was just wondering how you would reconstruct EEG using the leadfield, to try and verify how well it is modelling the data.
>> 
>> I have tried multiplying the source.avg.mom by the source.leadfield.
>> I wont clutter the email with code, however I can once requested.
>> 
>> I had a look at the spectra of the EEG and the spectra of the reconstructed EEG and they look   quite different.
>> 
>> Any help would be greatly appreciated.
>> 
>> Tyler
>> 
>> Sent from my iPad
>> _______________________________________________
>> fieldtrip mailing list
>> fieldtrip at donders.ru.nl
>> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
> _______________________________________________
> fieldtrip mailing list
> fieldtrip at donders.ru.nl
> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip