Imaging of the electrical activity of the brain: a colour display of EEG local conference

The authors study changes of EEG local coherence induced by cognitive activation of the brain in healthy subjects. Local coherence is a correlation coefficient between two electrical signal power spectra and may reflect the functional relationships between neighbouring brain areas. It is calculated on paired adjacent electrodes of the scalp EEG. The authors developed a colour display method allowing them to visualise the intensity and the distribution of coherence changes. The software creates maps of lateral and axial views of the brain on which meshes are drawn. The authors use a Gouraud like algorithm for colour interpolation on the polygons forming the meshes