mni2tal.m

function outpoints = mni2tal(inpoints)

% Converts coordinates from MNI brain to best guess

% for equivalent Talairach coordinates

% FORMAT outpoints = mni2tal(inpoints)

% Where inpoints is N by 3 or 3 by N matrix of coordinates

%  (N being the number of points)

% outpoints is the coordinate matrix with Talairach points

% Matthew Brett 10/8/99

 

dimdim = find(size(inpoints) == 3);

if isempty(dimdim)

  error(‘input must be a N by 3 or 3 by N matrix’)

end

if dimdim == 2

  inpoints = inpoints’;

end

 

% Transformation matrices, different zooms above/below AC

upT = spm_matrix([0 0 0 0.05 0 0 0.99 0.97 0.92]);

downT = spm_matrix([0 0 0 0.05 0 0 0.99 0.97 0.84]);

 

tmp = inpoints(3,:)<0;  % 1 if below AC

inpoints = [inpoints; ones(1, size(inpoints, 2))];

inpoints(:, tmp) = downT * inpoints(:, tmp);

inpoints(:, ~tmp) = upT * inpoints(:, ~tmp);

outpoints = inpoints(1:3, :);

if dimdim == 2

  outpoints = outpoints’;

end