The relation between lesions and localization of sources of slow biphasic complexes in encephalitis

Slow biphasic complexes (SBC) were found in the electroencephalogram (EEG) of patients with inflammations of the brain. We have developed an automated method to identify them and proved that they represent a sensitive marker of the severity of encephalitis. Here we focus on another property of SBCs, i.e., the localization of their sources. We present two encephalitic patients, showing lesions in the magnetic resonance images, which are either spread in the brain or focused on the left hemisphere, respectively. Applying a source localization algorithm to the identified SBCs, we found either a diffused or a left-focused distribution, respectively. This result further suggests a relation between neuroinflammation and appearance of SBCs, indicating that their distribution reflects in part the localization of brain lesions. This promising result extends the information that can be extracted from EEG, promoting the reduction of expensive or invasive measurements in encephalitic patients.