Automatic auditory processing deficits in schizophrenia and clinical high-risk patients: forecasting psychosis risk with mismatch negativity.
BACKGROUND
Only about one third of patients at high risk for psychosis based on current clinical criteria convert to a psychotic disorder within a 2.5-year follow-up period. Targeting clinical high-risk (CHR) individuals for preventive interventions could expose many to unnecessary treatments, underscoring the need to enhance predictive accuracy with nonclinical measures. Candidate measures include event-related potential components with established sensitivity to schizophrenia. Here, we examined the mismatch negativity (MMN) component of the event-related potential elicited automatically by auditory deviance in CHR and early illness schizophrenia (ESZ) patients. We also examined whether MMN predicted subsequent conversion to psychosis in CHR patients.


METHODS
Mismatch negativity to auditory deviants (duration, frequency, and duration + frequency double deviant) was assessed in 44 healthy control subjects, 19 ESZ, and 38 CHR patients. Within CHR patients, 15 converters to psychosis were compared with 16 nonconverters with at least 12 months of clinical follow-up. Hierarchical Cox regression examined the ability of MMN to predict time to psychosis onset in CHR patients.


RESULTS
Irrespective of deviant type, MMN was significantly reduced in ESZ and CHR patients relative to healthy control subjects and in CHR converters relative to nonconverters. Mismatch negativity did not significantly differentiate ESZ and CHR patients. The duration + frequency double deviant MMN, but not the single deviant MMNs, significantly predicted the time to psychosis onset in CHR patients.


CONCLUSIONS
Neurophysiological mechanisms underlying automatic processing of auditory deviance, as reflected by the duration + frequency double deviant MMN, are compromised before psychosis onset and can enhance the prediction of psychosis risk among CHR patients.
University of California, San Francisco, California; San Francisco Veterans Administration Medical Center, San Francisco, California.
Veronica B
VB
Perez
Yale University School of Medicine, New Haven, Connecticut.
Scott W
SW
Woods
University of California, San Francisco, California; San Francisco Veterans Administration Medical Center, San Francisco, California.
Brian J
BJ
Roach
University of California, San Francisco, California; San Francisco Veterans Administration Medical Center, San Francisco, California.
Judith M
JM
Ford
Yale University School of Medicine, New Haven, Connecticut.
Thomas H
TH
McGlashan
Yale University School of Medicine, New Haven, Connecticut.
Vinod H
VH
Srihari
University of California, San Francisco, California; San Francisco Veterans Administration Medical Center, San Francisco, California. Electronic address: daniel.mathalon@ucsf.edu.
Daniel H
DH
Mathalon
D000293:Adolescent; D016022:Case-Control Studies; D018450:Disease Progression; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000150:complications / Q000503:physiopathology*; D012306:Risk; D012559:Schizophrenia / Q000150:complications / Q000503:physiopathology*; D055815:Young Adult
Auditory cortex; clinical high-risk for psychosis; event-related potential; longitudinal; mismatch negativity; psychosis; schizophrenia