The reduced visual centrotemporal source, which followed the FRN as part of the generator pattern associated with a late occipital negativity, underscores the failure of schizophrenic patients to show response-related brain activation. Topography (vertex maximum) and time course of this distinct response-locked source suggest that it belongs to the family of Pe-like components reflecting different monitoring processes than the ERN/Ne but also of cingulate origin (e.g., Falkenstein et al., 2000; Vocat et al., 2008). The late occipital negativity, which has frequently been observed in visual recognition memory tasks showing an inverted old/new effect (cf. Johansson & Mecklinger, 2003), was also reduced in the visual modality for schizophrenic patients. Despite this overall reduction in amplitude, no abnormalities were found for the overlapping inverted late episodic memory effect over centroparietal midline sites consistent with a generator pattern posteriorly along the cingulate sulcus (cf. Kayser et al., 2007). However, more research is clearly needed on how different response-related ERP components relate to and reflect impaired performance monitoring in schizophrenia.
