title: Overlapping auditory M100 and M200 abnormalities in schizophrenia and bipolar disorder: a MEG study.
abstract: OBJECTIVE
  Schizophrenia and bipolar disorder share common etiological factors and pathophysiological pathways and have overlapping clinical features. Only few studies have directly compared early auditory information processing in the two disorders. The objective of this study was to investigate the M100 and M200 auditory responses in patients with schizophrenia and bipolar disorder and compare them with healthy controls using magnetoencephalography (MEG).
  
  
  METHODS
  Whole-head MEG data were acquired during an auditory oddball paradigm in 24 schizophrenia patients, 26 bipolar I disorder patients, and 31 healthy controls. The strengths and latencies of M100 and M200 in both hemispheres and the dipole source localizations were investigated from the standard stimuli.
  
  
  RESULTS
  The M100 and M200 dipolar sources were localized to the left and right posterior portion of the superior temporal gyrus (STG) in all the subjects. An asymmetric pattern of M100 and M200 auditory response with more anterior sources in the right STG was observed in the healthy controls. However, both the schizophrenia and bipolar disorder patients showed a symmetric M100 and M200 source pattern. When compared with the healthy control group, both patient groups showed significantly reduced M100 and M200 source strength in both hemispheres.
  
  
  CONCLUSIONS
  Our study suggests that early auditory information processing deficits may be similar in schizophrenia and bipolar disorder and may be related to abnormalities of the STG.
authors.affiliation: Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China; Clinical Experimental Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. Electronic address: johneil@vip.sina.com.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Psychiatry, First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Jia
authors.affiliation: Medical Imaging Center, Guangdong 999 Brain Hospital, Guangzhou 510510, China.
authors.forename: Yigang
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Psychiatry, First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Shuming
authors.initials: S
authors.lastname: Zhong
authors.affiliation: Medical Imaging Center, Guangdong 999 Brain Hospital, Guangzhou 510510, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Medical Imaging Center, Guangdong 999 Brain Hospital, Guangzhou 510510, China.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Wang
authors.affiliation: Medical Imaging Center, Guangdong 999 Brain Hospital, Guangzhou 510510, China.
authors.forename: Yufang
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Medical Imaging Center, Guangdong 999 Brain Hospital, Guangzhou 510510, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. Electronic address: cjr.huangli@vip.163.com.
authors.forename: Li
authors.initials: L
authors.lastname: Huang
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D001714:Bipolar Disorder / Q000503:physiopathology*; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000503:physiopathology*; D055815:Young Adult
keywords: Bipolar disorder; M100; M200; Magnetoencephalography; Schizophrenia