J Korean Soc Biol Psychiatry.  2003 Nov;10(2):168-176.

The P300 Source Localization in the Patients with Obsessive-Compulsive Disorder using the LORETA Imaging and SPM

• Park SK
• Choi JS
• Yu SY
• Lee BR
• Kang SS
• Roh KS
• Ha TH
• Kwon JS

Abstract

OBJECTIVES
We investigated the characteristics of P300 generators in obsessive-compulsive disorder(OCD) patients by using voxel-based statistical parametric mapping of current density images.
METHODS
P300 generators, produced by a rare target tone of 1500Hz under a frequent non-target tone of 1,000Hz, were measured in 15 right-handed OCD patients and 15 controls. Low Resolution Electromagnetic Tomography(LORETA), using a realistic head model of the boundary element method based on individual MRI, was applied to the 128-channel EEG. Statistical parametric mapping(SPM) was applied for the statistical analysis.
RESULTS
We found that both groups had the mean current density of P300 in the parietal, temporal and prefrontal lobe. There was a trend for decreased current density in the prefrontal area in OCD patients. The statistical comparison showed current density increase in the supraparietal area, a statistically significant longer P300 latency and a trend for reduced P300 amplitude in OCD patients.
CONCLUSION
It suggests that P300 source of both groups exists in multiple brain regions at the same time. And both groups had no statistically significant differences in the current density of P300 except for increased current density in the supraparietal area in OCD patients. But, considering the statistically significant longer P300 latency, a trend for reduced P300 amplitude and relative mean current density reduction in the prefrontal area in OCD patients, this study suggests that the frontal lobe may have a reduced normal inhibitory process in OCD patients.

MeSH Terms

Brain
Electroencephalography
Frontal Lobe
Head
Humans
Insulator Elements
Magnetic Resonance Imaging
Magnets
Obsessive-Compulsive Disorder*
Rabeprazole