title: Source imaging of P300 auditory evoked potentials and clinical correlations in patients with posttraumatic stress disorder.
abstract: OBJECTIVE
  Posttraumatic stress disorder (PTSD) is associated with abnormal information processing. The P300 component of event-related potentials (ERPs) is known to be a useful marker of information processing. The purposes of this study were to determine the P300 current source density in PTSD patients, and its relationship with symptom severity.
  
  
  METHODS
  ERPs were recorded in 30 PTSD patients and 33 healthy controls while participants were performing the auditory oddball task. We compared P300 current source density data--obtained by standardized low-resolution brain electromagnetic tomography (sLORETA)--between the two groups. The correlation between P300 current source density and clinical symptoms (as evaluated using the Korean version of the Structured Interview for PTSD--K-SIPS and Davidson Trauma Scale--K-DTS) was conducted.
  
  
  RESULTS
  In PTSD patients, the current source density of P300 is significantly reduced in the inferior frontal gyrus, precentral gyrus, insula, and anterior cingulate compared to healthy controls. Total K-DTS scores were correlated with the P300 current source density in the posterior cingulate gyrus. The K-SIP B items (re-experiencing) and K-SIB D items (increased arousal) were positively correlated with P300 current source densities in several brain regions located in the frontal, parietal, and temporal lobe (p<0.05). Conversely, the K-SIP C items (avoidance and numbing) were negatively correlated with P300 current source densities in the superior and middle frontal gyri in the frontal lobes (p<0.05).
  
  
  CONCLUSIONS
  The P300 current source densities reflected the pathophysiology of PTSD patients. PTSD symptoms were related to different neural activities, depending on their symptom characteristics.
authors.affiliation: Department of Psychiatry, Chonnam National University Hospital, Gwangju, Republic of Korea.
authors.forename: Kyung-Yeol
authors.initials: KY
authors.lastname: Bae
authors.forename: Do-Won
authors.initials: DW
authors.lastname: Kim
authors.forename: Chang-Hwan
authors.initials: CH
authors.lastname: Im
authors.forename: Seung-Hwan
authors.initials: SH
authors.lastname: Lee
mesh_terms: D000063:Accidents, Traffic; D000328:Adult; D001303:Auditory Cortex / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D012720:Severity of Illness Index; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology*