title: ERPs in schizophrenia: effects of antipsychotic medication.
abstract: Thirty unmedicated schizophrenics were compared to 29 age-matched controls on auditory and visual event-related brain potential (ERP) paradigms. Twenty-one of these patients were tested again after 1 week on placebo and after 4 weeks on antipsychotic medication. Before treatment, N1, N2, and P3 components of the auditory ERP were smaller in the schizophrenics than in the controls. Although visual N2 was smaller in schizophrenics, visual P3 was not. In spite of significant clinical improvement with antipsychotic treatment, amplitudes of auditory and visual N1, N2, and P3 were not significantly changed. Higher blood levels of antipsychotic medication were related to reductions in auditory P3 latency, however. In addition, higher levels of cerebrospinal fluid (CSF) MHPG (methoxyhydroxyphenylglycol) were associated with larger auditory N1s and larger auditory and visual P3s, suggesting an influence of arousal on these components in schizophrenics. In spite of this influence, reduction of the auditory P3 in schizophrenia is an enduring trait of the disease, which is not affected by antipsychotic medication or clinical improvement.
authors.affiliation: Department of Veterans Affairs Medical Center, Palo Alto, CA 94304.
authors.forename: J M
authors.initials: JM
authors.lastname: Ford
authors.forename: P M
authors.initials: PM
authors.lastname: White
authors.forename: J G
authors.initials: JG
authors.lastname: Csernansky
authors.forename: W O
authors.initials: WO
authors.lastname: Faustman
authors.forename: W T
authors.initials: WT
authors.lastname: Roth
authors.forename: A
authors.initials: A
authors.lastname: Pfefferbaum
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D001143:Arousal / Q000187:drug effects* / Q000502:physiology; D002540:Cerebral Cortex / Q000187:drug effects / Q000503:physiopathology; D004298:Dopamine / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004569:Electroencephalography / Q000187:drug effects; D005072:Evoked Potentials, Auditory / Q000187:drug effects* / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000187:drug effects* / Q000502:physiology; D006220:Haloperidol / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D020891:Raclopride; D012457:Salicylamides / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D012559:Schizophrenia / Q000188:drug therapy* / Q000503:physiopathology; D012565:Schizophrenic Psychology
chemical_list: D014150:Antipsychotic Agents; D012457:Salicylamides; D020891:Raclopride; D006220:Haloperidol; D004298:Dopamine