Impairment not only in remembering but also in knowing previously seen faces and words in schizophrenia

Patients with schizophrenia have pronounced deficits in face recognition memory that severely hamper their social skills. The functional mechanisms of these impairments remain unknown. According to the dual-process theory, recognition memory comprises two distinct components: recollection and familiarity. Studies using the Remember/Know procedure in patients with schizophrenia showed impairments in conscious recollection as measured by remember responses, but not in familiarity as measured by know responses. Unfortunately, none of these studies used face material. We investigated both recognition memory components using words and faces and the 'Remember/Know' procedure in 25 patients with schizophrenia and 24 control participants. In the same task, size congruency of stimuli was manipulated between the study and test phases to have a selective impact on know responses for faces. Patients reported fewer remember responses than controls. Size changes between the study and the test affected know responses in controls but not in patients. These results reveal that patients with schizophrenia are impaired in terms of their ability to recollect details about previously seen faces as they are for words.