Strong left parietal old/new effects for words and faces were present in both healthy adults and schizophrenic patients, likely reflecting conscious recollection processes associated with retrieval of contextual information (e.g., Friedman and Johnson, 2000; Rugg and Curran, 2007). The region for this old-greater-than-new source is entirely consistent with conventional ERP findings (e.g., Allan et al., 1998; Ally et al., 2008) as well as neuroimaging evidence implicating old/new effects for the lateral posterior parietal cortex (e.g., Wagner et al., 2005; Cabeza, 2008). Schizophrenia patients, however, revealed marked topographic abnormalities of old/new effects for words in that their lateral old/new sources were significantly reduced while their medial parietal old/new effects were largely preserved. This precisely replicates our previous CSD findings of abnormal late parietal old/new effects in schizophrenia for visually-presented words (Kayser et al., 2009). The current study adds that this lateral reduction is less evident for faces. Moreover, late parietal old/new effects were strongly left-lateralized in healthy adults across tasks, which is the typical topographical finding (e.g., Johnson, 1995; Allan et al., 1998; Friedman and Johnson, 2000), but were less asymmetric in patients (cf. Kayser et al., 1999, 2009).
