PMID- 12711232
OWN - NLM
STAT- MEDLINE
DCOM- 20030910
LR  - 20191025
IS  - 1350-4533 (Print)
IS  - 1350-4533 (Linking)
VI  - 25
IP  - 5
DP  - 2003 Jun
TI  - Effect of brain damage and source location on left-right asymmetry of visual 
      evoked potentials in a realistic model of the head.
PG  - 349-59
AB  - The left-right asymmetry of visual evoked potentials (VEP) was studied using a 
      realistic three-dimensional model of the head, constructed from CT scans. The 
      integral equation describing the potential distribution due to an inner 
      current-dipole (simulating the VEP source), inside the biological volume 
      conductor (the head) was solved numerically using the finite volume method. The 
      effect of several structural parameters, such as the natural head geometry, the 
      location and orientation of the current source, and conductivity changes 
      (simulating a brain damage) on the VEP asymmetry was examined. The results 
      revealed that the natural anatomical asymmetry presented in a normal head induces 
      some degree of VEP asymmetry (up to 0.42% at the occipital electrodes), yet the 
      major cause of left-right asymmetry is due to asymmetrical location of the 
      source: up to 6.53% in the O(2)-O(1) electrodes for an angular shift of 3 degrees 
      to the left. It was also found that conductivity changes inside the head have a 
      smaller effect on the VEP asymmetry (up to 3.35% in hemorrhaged brain compared to 
      1.96% in the normal brain at the C(4)-C(3) electrodes). These findings may help 
      in better understanding VEP sources of asymmetry, originating not only due to 
      cerebral functionality, but from structural parameters as well.
FAU - Radai, M M
AU  - Radai MM
AD  - Biomedical Engineering Department, Faculty of Engineering, Tel-Aviv University, 
      Israel.
FAU - Rosenfeld, M
AU  - Rosenfeld M
FAU - Abboud, S
AU  - Abboud S
LA  - eng
PT  - Journal Article
PL  - England
TA  - Med Eng Phys
JT  - Medical engineering & physics
JID - 9422753
SB  - IM
MH  - Action Potentials
MH  - Brain/diagnostic imaging/*physiopathology
MH  - Brain Damage, Chronic/*physiopathology
MH  - Brain Mapping/*methods
MH  - Computer Simulation
MH  - Electroencephalography/methods
MH  - *Evoked Potentials, Visual
MH  - Head/diagnostic imaging/physiopathology
MH  - Humans
MH  - Imaging, Three-Dimensional/methods
MH  - Male
MH  - Middle Aged
MH  - *Models, Neurological
MH  - Neurons
MH  - Radiography
MH  - Visual Cortex/physiopathology
EDAT- 2003/04/25 05:00
MHDA- 2003/09/11 05:00
CRDT- 2003/04/25 05:00
PHST- 2003/04/25 05:00 [pubmed]
PHST- 2003/09/11 05:00 [medline]
PHST- 2003/04/25 05:00 [entrez]
AID - S135045330300033X [pii]
AID - 10.1016/s1350-4533(03)00033-x [doi]
PST - ppublish
SO  - Med Eng Phys. 2003 Jun;25(5):349-59. doi: 10.1016/s1350-4533(03)00033-x.