MAGNETOENCEPHALOGRAPHY IN STUDIES OF HUMAN COGNITIVE BRAIN-FUNCTION

Magnetoencephalography provides a new dimension to the functional imag ing of the brain. The cerebral magnetic fields recorded noninvasively enable the accurate determination of locations of cerebral activity wi th an uncompromized time resolution. The first whole-scalp sensor arra ys have just recently come into operation, and significant advances ar e to be expected in both neurophysiological and cognitive studies, as well as in clinical practice. However, although the accuracy of locati ng isolated sources of brain activity has improved, identification of multiple simultaneous sources can still be a problem. Therefore, attem pts are being made to combine magnetoencephalography with other brain- imaging methods to improve spatial localization of multiple sources an d, simultaneously, to achieve a more complete characterization of diff erent aspects of brain activity during cognitive processing. Owing to its good time resolution and considerably better spatial accuracy than that provided by EEG, magnetoencephalography holds great promise as a tool for revealing information-processing sequence of the human brain .