P300 subcomponents reflect different aspects of psychopathology in schizophrenia.
BACKGROUND
The aim of the study was to investigate abnormalities of P300 subcomponents in schizophrenic patients as well as relationships between these subcomponents and positive versus negative schizophrenic symptoms.


METHODS
Nineteen schizophrenic patients and 19 healthy controls were tested with an auditory event-related potential oddball paradigm designed to elicit the P300. The P300 data were analyzed by separating P300 subcomponents with a recently developed dipole source model.


RESULTS
Compared to healthy controls, schizophrenic patients showed reduced P300 amplitudes of the temporo-basal dipoles, corresponding mainly to P3b. Positive symptoms of the Positive and Negative Syndrome Scale correlated positively with the temporo-basal but not with temporo-superior dipole P300 activities, whereas negative symptoms correlated positively with the temporo-superior but not with temporo-basal dipole activities.


CONCLUSIONS
The P300 subcomponents separated with the dipole model are affected in a different manner by positive versus negative symptoms. Furthermore, the positive correlation between the severity of psychopathology and the P300 amplitudes of the different dipole activities appears to be a state-dependent effect, which has to be separated from the P300 amplitude reduction as a trait marker in schizophrenic patients.
Frodl-Bauch
T
T
Department of Clinical Neurophysiology, EEG, Psychiatric Hospital, Ludwig Maximilians Universität, Munich, Germany.
Gallinat
J
J
Meisenzahl
E M
EM
Möller
H J
HJ
Hegerl
U
U
D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012565:Schizophrenic Psychology
D014150:Antipsychotic Agents