Redundancy of independent component analysis in four common types of childhood epileptic seizure.

SUMMARY Independent component analysis (ICA) has recently been applied to epileptic seizure in the EEG. In this paper, the authors show how the fundamental axioms required for ICA to be valid are broken. Four common cases of childhood seizure are presented and assessed for stationarity and an eigenvalue analysis is applied. In all cases, for the stationary sections of data the eigenvalue analysis yields results that imply the signals are coming from a source-rich environment, thus yielding ICA inappropriate when applied to the four common types of childhood seizure. The results suggest that it is not appropriate to apply ICA or source localization from independent components in these four common cases of epilepsy, because the spurious independent components determined by ICA could lead to a spurious localization of the epilepsy. If surgery were to follow, it could result in the incorrect treatment of a healthy localized region of the brain.