MEG localizes brain activity better than EEG because skull distorts signals less

Evidence

In electroencephalography (EEG), electrodes are placed on the scalp, and the electric potential in relation to a reference voltage measured from the subject is recorded with time. The neural activity during and after the stimulus causes small changes in the recorded voltages. The benefit of EEG is that it responds quickly to changes in brain activity. However, localizing the sources of activity and differentiating between the contributions of brain areas is difficult using EEG. Another, somewhat similar method is magnetoencephalography (MEG), where the magnetic fields caused by electrical currents in neurons are recorded with very sensitive magnetometers. It has better resolution in localizing the activity within the brain than EEG has, because it suffers less from distortions caused by the scalp and skull. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 815

Categorization

Category: Causal Relationships

• DEFINE: Clarifies the functional difference between EEG and MEG as complementary noninvasive brain recording methods.