title: Associated deficits in mismatch negativity generation and tone matching in schizophrenia.
abstract: OBJECTIVE
  Schizophrenia is associated with deficits in mismatch negativity (MMN) generation and in the ability to match two tones following brief delay. Both deficits reflect impaired early cortical processing of auditory information. However, the relationship between deficits in MMN generation and tone matching performance in schizophrenia has not been established.
  
  
  METHODS
  MMN and tone matching performance was evaluated in 12 schizophrenic subjects and 12 similar aged controls. A pitch separation known to produce non-ceiling performance in patients (5% Deltaf) was used. Narrow band filtering of MMN data was used to enhance signal-to-noise ratio.
  
  
  RESULTS
  Schizophrenic subjects showed impairments in both MMN generation and tone matching performance. The two deficits were significantly correlated across subjects. In addition, decreased MMN amplitude and poorer tone matching performance correlated with increased severity of negative symptoms.
  
  
  CONCLUSIONS
  These findings support the concept that similar neurophysiological mechanisms underlie MMN and tone matching deficits in schizophrenia. Further, they indicate that increased sensitivity to environmental change may be related to social withdrawal and other negative symptoms in schizophrenia.
authors.affiliation: Program in Cognitive Neuroscience and Schizophrenia, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg, NY 10962, USA. javitt@nki.rfmh.org
authors.forename: D C
authors.initials: DC
authors.lastname: Javitt
authors.forename: A
authors.initials: A
authors.lastname: Shelley
authors.forename: W
authors.initials: W
authors.lastname: Ritter
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D006801:Humans; D008297:Male; D012559:Schizophrenia / Q000503:physiopathology*