The basic CSD-PCA factor structure for the novelty oddball task agrees with that observed for other oddball tasks. Factors with comparable topographies for all classes of stimuli included N1, a bilateral sink/source pair consistent with activation of primary auditory cortex within the Sylvian fissure, followed by temporal N1, a bilateral sink topography consistent with generators on the lateral surface of the temporal lobes. Target-related factors included N2 (lateral and midline frontal sinks), P3b (parietal source), and a later, response-related factor (F – CP+) that corresponds to a frontally inverting, slow wave contribution of the late positive complex, and that resembles a spatial factor described by Spencer, Wijesinghe, Dien, and Donchin (1999).
