Mismatch negativity and cognitive performance in the course of schizophrenia.

•MMN is reduced in schizophrenia patients, independent of illness stage, but inconspicuous in the present at-risk sample.•At-risk individuals exhibit cognitive deficits like schizophrenics and cognitive performance predicts symptom severity.•MMN is proposed as marker for manifest psychosis and cognitive performance as marker for non-specific psychopathology.