Add the following to your Matlab startup.m file:
%---------------------- MNE --------------------------%
mnehome = getenv('MNE_ROOT');
mnematlab = sprintf('%s/share/matlab',mnehome);
if (exist(mnematlab) == 7)
path(path,mnematlab);
end
clear mnehome mnematlab;
%-----------------------------------------------------%If you run the MNE setup script before starting Matlab, it will automatically add the paths to the MNE tools.