TY - JOUR
T1 - Instability of prefrontal signal processing in schizophrenia
AU - Winterer, Georg
AU - Musso, Francesco
AU - Beckmann, Christian
AU - Mattay, Venkata
AU - Egan, Michael F.
AU - Jones, Douglas W.
AU - Callicott, Joseph H.
AU - Coppola, Richard
AU - Weinberger, Daniel R.
PY - 2006/11
Y1 - 2006/11
N2 - Objective: Prefrontal dysfunction is considered a fundamental characteristic of schizophrenia. Recent electrophysiological evidence points to a major instability of signal processing in prefrontal cortical microcircuits because of reduced phase-synchronization (i.e., an increased stimulus-related variability [noise] of single-trial responses in the spatial and time domain). The authors used functional magnetic resonance imaging (fMRI) during a visual two-choice reaction task in order to measure, with higher topographic accuracy, signal stability in patients with schizophrenia and its relationship to more traditional measures of activation. Method: Twelve clinically stable inpatients with schizophrenia and 16 matched comparison subjects were evaluated. Event-related blood-oxygen-level-dependent responses were subjected to an analysis of residual noise variance and to independent data dimension independent component analysis in the medial prefrontal cortex. Results: In patients with schizophrenia, the authors found increased residual noise variance of the blood-oxygen-level-dependent response that predicted the level of prefrontal activation in these subjects. In the left hemisphere, residual noise variance strongly correlated with psychotic symptoms. Independent component analysis revealed a "fractionized" and unfocussed pattern of activation in patients. Conclusions: These findings suggest that unstable cortical signal processing underlies classic abnormal cortical activation patterns as well as psychosis in schizophrenia.
AB - Objective: Prefrontal dysfunction is considered a fundamental characteristic of schizophrenia. Recent electrophysiological evidence points to a major instability of signal processing in prefrontal cortical microcircuits because of reduced phase-synchronization (i.e., an increased stimulus-related variability [noise] of single-trial responses in the spatial and time domain). The authors used functional magnetic resonance imaging (fMRI) during a visual two-choice reaction task in order to measure, with higher topographic accuracy, signal stability in patients with schizophrenia and its relationship to more traditional measures of activation. Method: Twelve clinically stable inpatients with schizophrenia and 16 matched comparison subjects were evaluated. Event-related blood-oxygen-level-dependent responses were subjected to an analysis of residual noise variance and to independent data dimension independent component analysis in the medial prefrontal cortex. Results: In patients with schizophrenia, the authors found increased residual noise variance of the blood-oxygen-level-dependent response that predicted the level of prefrontal activation in these subjects. In the left hemisphere, residual noise variance strongly correlated with psychotic symptoms. Independent component analysis revealed a "fractionized" and unfocussed pattern of activation in patients. Conclusions: These findings suggest that unstable cortical signal processing underlies classic abnormal cortical activation patterns as well as psychosis in schizophrenia.
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U2 - 10.1176/ajp.2006.163.11.1960
DO - 10.1176/ajp.2006.163.11.1960
M3 - Article
C2 - 17074948
AN - SCOPUS:33751331472
SN - 0002-953X
VL - 163
SP - 1960
EP - 1968
JO - American Journal of Psychiatry
JF - American Journal of Psychiatry
IS - 11
ER -