D9 Magnetoencephalography (MEG)

Title

MEG records the magnetic field generated by the same intracellular dipolar currents that produce the EEG signal (direct extension of D01), but since the magnetic field is not distorted by the heterogeneous conductivity of the skull and scalp, it offers a more precise localization of sources, with special sensitivity to sources oriented tangentially with respect to the sensor. The reconstruction of cortical activity from the recorded magnetic field is typically performed using spatial filtering techniques (beamforming), which estimate at each point in space the optimal combination of sensors that minimizes the variance of unwanted sources without distorting the source of interest. MEG combines a very high temporal resolution, limited only by the sampling rate, with spectral and phase connectivity analyzes (direct extension of the coherence and synchronization of E09) analogous to those of EEG but with better spatial resolution.

ID:4305