1993 Volume 11 Issue 1 Pages 23-30
Dipole Tracing (DT) method was applied to estimate the equivalent current dipoles (ECD) of the focal spike and slow wave complex (SWC).
Scalp EEGs were recorded in five patients with localization-related epilepsies (four cases were temporal lobe and the other was frontal lobe epilpsy). The SWC was devided into three components for DT analysis; negative spike component, trough (positive component) and slow wave component. Estimated ECDs of the three components were closely located to each other at a districted regional brain area on the dominant side of the spikes. These results suggested that three components of the focal SWC might be originated from closely located electrical generators in the brain.
Furthermore it was observed that the vectors of ECDs of the spike and the slow wave components indicated almost the same direction, but that of the positive component pointed a direction almost opposite to them. It was speculated that the spike component and the positive component in the scalp EEG might reflect the excitatory and inhibitory electrical activities, respectively.