Magnetic Signals in the Study of Human Brain Dynamics

Abstract

Magnetoencephalography provides a totally noninvasive method to study brain function with a millisecond time resolution. The measured signal alone gives an approximate site, intensity, and orientation of the current flow in the cortex. More accurate information is obtained by applying standard source models with physiological constraints. The MEG signals are readily combined with the images obtained by other techniques, such as MRI or PET.

To increase our understanding of the human brain, an obvious approach is to characterize and quantify the sequences of cortical events related to repeated stimuli or tasks with good combined temporal and spatial resolution. Magnetic signals thus open one important window for assessing brain function.