title: P600 alteration of syntactic language processing in patients with bipolar mania: Comparison to schizophrenic patients and healthy subjects.
abstract: Disturbances in thought, speech, and linguistic processing are frequently observed in bipolar manic patients, but the underlying neurophysiological mechanisms are not well understood. P600 is a distinct, positive event-related potential component elicited by syntactic violations. Using the P600 ERP, we examined neural processing of syntactic language comprehension in patients with bipolar mania compared to patients with schizophrenia and healthy people.
  
  
  
  P600s were recorded from 21 manic patients with bipolar disorder, 26 patients with schizophrenia, and 29 healthy subjects during the presentation of 120 auditory sentences with syntactic violations or non-violations. Subjects were asked to judge whether each sentence was correct or incorrect.
  
  
  
  Patients with mania and schizophrenia had significantly smaller P600 amplitudes associated with syntactic violations compared with healthy subjects. There was no difference in P600 amplitude between patient groups. For behavioral performance, patients with schizophrenia had significantly less accurate rates and longer reaction times compared with healthy subjects, whereas manic patients exhibited no significant differences in accuracy and only showed increased reaction times in comparison with healthy subjects.
  
  
  
  Psychotropic drug usage and small sample size.
  
  
  
  Patients with bipolar mania have reduced P600 amplitude, comparable to patients with schizophrenia. Our findings may represent the first neurophysiological evidence of abnormal syntactic linguistic processing in bipolar mania.
authors.affiliation: Department of Psychiatry, Jin Hospital, Bucheon, Republic of Korea.
authors.forename: Chang Woo
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, Hallym University College of Medicine, Hwaseong, Republic of Korea.
authors.forename: Sung Hwa
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea.
authors.forename: Miseon
authors.initials: M
authors.lastname: Shim
authors.affiliation: Department of Psychiatry, Seoul National Hospital, Seoul, Republic of Korea.
authors.forename: Vin
authors.initials: V
authors.lastname: Ryu
authors.affiliation: Department of Psychiatry, Seoul Bukbu Hospital, Seoul, Republic of Korea.
authors.forename: Ra Yeon
authors.initials: RY
authors.lastname: Ha
authors.affiliation: Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea; Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea. Electronic address: chs0225@yuhs.ac.
authors.forename: Hyun-Sang
authors.initials: HS
authors.lastname: Cho
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy / Q000503:physiopathology*; D032882:Comprehension; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007802:Language; D008037:Linguistics; D008297:Male; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D013060:Speech; D013850:Thinking
chemical_list: D014150:Antipsychotic Agents
keywords: Bipolar mania; Event-related potential; P600; Schizophrenia; Syntactic processing