Check the quality of the anatomical coregistration
The following code makes a number of figures that can be used as quality control for the procedure to coregister the MRI with the MEG.
Please note that this is an example where the coregistration was not completely correct. The head is tilted to the left.
%% load the required data load headmodel_mri.mat load headshapeMEG.mat % from the fiff file load mri_resliced.mat % resliced load mri_segmented.mat load sens.mat %% figure 1 figure ft_plot_sens(sens, 'unit', 'mm') ft_plot_headshape(headshapeMEG, 'unit', 'mm') ft_plot_vol(headmodel_mri, 'unit', 'mm') ft_plot_axes([], 'unit', 'mm');
%% figure 2, MRI anatomy and brain segmentation cfg = []; cfg.anaparameter = 'anatomy'; cfg.funparameter = 'brain'; cfg.location = [0 0 60]; ft_sourceplot(cfg, mri_segmented)
%% figure 3 and 4, MRI anatomy and headmodel location = [0 0 60]; figure ft_plot_ortho(mri_resliced.anatomy, 'transform', mri_resliced.transform, 'location', location, 'intersectmesh', headmodel_mri.bnd) figure ft_plot_montage(mri_resliced.anatomy, 'transform', mri_resliced.transform, 'intersectmesh', headmodel_mri.bnd)
%% figure 5, MRI scalp surface and polhemus headshape cfg = []; cfg.tissue = 'scalp'; cfg.method = 'isosurface'; cfg.numvertices = 10000; scalp = ft_prepare_mesh(cfg, mri_segmented); figure ft_plot_mesh(scalp, 'facecolor', 'skin') lighting phong camlight left camlight right material dull alpha 0.5 ft_plot_headshape(headshapeMEG, 'vertexcolor', 'k');
%% figure 6, MRI and anatomical landmarks figure for i=1:3 subplot(2,2,i) title(headshapeMEG.fid.label{i}); location = headshapeMEG.fid.pos(i,:); ft_plot_ortho(mri_resliced.anatomy, 'transform', mri_resliced.transform, 'style', 'intersect', 'location', location, 'plotmarker', location, 'markersize', 5, 'markercolor', 'y') end
%% figure 7, MRI scalp surface and anatomical landmarks figure ft_plot_mesh(scalp, 'facecolor', 'skin') lighting phong camlight left camlight right material dull alpha 0.3 ft_plot_mesh(headshapeMEG.fid, 'vertexcolor', 'k', 'vertexsize', 10);