BESA Research 5.3 includes CLARA (Classical LORETA Analysis Recursively Applied), a new iterative 3D source imaging method. CLARA is an iterative application of weighted LORETA images with a reduced source space in each iteration.
Iterative 3D imaging methods aim at reducing the blurring of focal brain activity that is inherent to distributed imaging techniques while keeping the advantage of a predefined distributed source model.
In the figure, a CLARA image has been computed for an N100 response to auditory stimulus in an oddball experiment. The 3D image is superimposed to the individual MRI of the subject. Compared to traditional single LORETA and other 3D imaging techniques, the CLARA image provides a rather focal display of the active brain areas.