Dear Stephan,
This is already implemented in the source extraction functionality
that you can access via batch. If you specify radius of 0 you will get
just one dipole, but this might not be a good idea as the signal you
are really interested in might be projected on a different dipole
because of the orientations. So I'd suggest to take some radius around
your location of interest.
Best,
Vladimir
On Tue, Jul 3, 2012 at 4:38 PM, Stephan Moratti <[log in to unmask]> wrote:
> Hi everybody,
>
> I have a question: I would like to reconstruct single trial time series of a
> dipole location on my surface mesh that I have used before for source
> reconstruction using MSP in SPM8.
>
> I see in the code the following parameters but later get lost:
>
> % inversion parameters
> %--------------------------------------------------------------------------
> J = model.inverse.J; % Trial average MAP estimate
> T = model.inverse.T; % temporal projector
> U = model.inverse.U; % spatial projector[s]
> Is = model.inverse.Is; % Indices of ARD vertices
> Ic = model.inverse.Ic; % Indices of channels
> It = model.inverse.It; % Indices of time bins
> pst = model.inverse.pst; % peristimulus time (ms)
> Nd = model.inverse.Nd; % number of mesh dipoles
> Nb = size(T,1); % number of time bins
> Nc = size(U,1); % number of channels
> Nw = size(woi,1); % number of contrast windows
> Nj = numel(J);
>
>
> So which of these matrices I would have to multiply with my single trial
> data to reconstruct the time series of a specific dipole (mesh) location. If
> I do J*T' I get the evoked response. Is there a kind of inverse operator
> that can be multiplied with the single trial sensor data?
>
> Thanks in advance,
>
> Best,
>
> Stephan
>
>
> ________________________________________________________
> Stephan Moratti, PhD
>
> see also: http://web.me.com/smoratti/
>
> Universidad Complutense de Madrid
> Facultad de Psicología
> Departamento de Psicología Básica I
> Campus de Somosaguas
> 28223 Pozuelo de Alarcón (Madrid)
> Spain
>
> and
>
> Center for Biomedical Technology
> Laboratory for Cognitive and Computational Neuroscience
> Parque Científico y Tecnológico de la Universidad Politecnica de Madrid
> Campus Montegancedo
> 28223 Pozuelo de Alarcón (Madrid)
> Spain
>
>
> email: [log in to unmask]
> Tel.: +34 679219982
>
>
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