Study of the origin of short- and long-latency SSEP during recovery from brain ischemia in a rat model.
Somatosensory evoked potentials (SSEPs) have been established as an electrophysiological tool for the prognostication of neurological outcome in patients with hypoxic-ischemic brain injury. The early and late responses in SSEPs reflect the sequential activation of neural structures along the somatosensory pathway. This study reports that the SSEP can be separated into early (short-latency, SL) and late (long-latency, LL) responses using independent component analysis (ICA), based on the assumption that these components are generated from different neural sources. Moreover, this source separation into the SL and LL components allows analysis of electrophysiological response to brain injury, even when the SSEPs are severely distorted and SL and LL components get mixed. With the help of ICA decomposition and corrected peak estimation, the latency of LL-SSEP is shown to be predictive of long-term neurological outcome. Further, it is shown that the recovery processes of SL- and LL-SSEPs follow different dynamics, with the SL-SSEP restored earlier than LL-SSEP. We predict that the SL- and LL-SSEPs reflect the timing of the progression of evoked response through the thalamocortical pathway and as such respond differently depending upon injury and recovery of the thalamic and cortical regions, respectively.
Wu
Dan
D
Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Anastassios
Bezerianos
B
Xiong
Wei
W
Madhok
Jai
J
Jia
Xiaofeng
X
Thakor
Nitish V
NV
D000818:Animals; D001784:Blood Gas Analysis; D001794:Blood Pressure / Q000502:physiology; D002545:Brain Ischemia / Q000150:complications / Q000503:physiopathology*; D004567:Electrodes, Implanted; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D006323:Heart Arrest / Q000150:complications; D008297:Male; D009422:Nervous System Diseases / Q000209:etiology; D009434:Neural Pathways / Q000502:physiology; D025341:Principal Component Analysis; D051381:Rats; D017208:Rats, Wistar; D013003:Somatosensory Cortex / Q000502:physiology
Resuscitation. 2008 Mar;76(3):431-42
17936492
J Neurophysiol. 2002 Oct;88(4):1924-32
12364518
Mov Disord. 2000;15 Suppl 1:14-21
10755267
Clin Neurophysiol. 2000 Oct;111(10):1779-87
11018492
Neurology. 2006 Jul 25;67(2):203-10
16864809
Neuroscience. 1994 Dec;63(3):711-24
7898672
Proc Natl Acad Sci U S A. 2003 May 13;100(10):6174-9
12719546
Lancet. 1993 Apr 3;341(8849):855-8
8096562
Proc Natl Acad Sci U S A. 1998 Feb 3;95(3):803-10
9448244
J Cereb Blood Flow Metab. 1995 Nov;15(6):1032-9
7593335
Neurosci Lett. 2001 Apr 20;302(2-3):137-40
11290406
J Neurosci Methods. 2004 Mar 15;134(1):9-21
15102499
Neuroscience. 2002;115(3):917-29
12435429
Neural Comput. 1995 Nov;7(6):1129-59
7584893
Clin Neurophysiol. 2008 May;119(5):1051-61
18343719
Neurourol Urodyn. 2009;28(4):320-4
19090588
AJNR Am J Neuroradiol. 1998 Apr;19(4):648-52
9576649
Vision Res. 1997 Dec;37(23):3327-38
9425547
Neural Netw. 2000 May-Jun;13(4-5):411-30
10946390
Brain Res. 2006 Sep 21;1111(1):166-75
16919609
Trends Neurosci. 2001 Oct;24(10):595-601
11576674
Proc Natl Acad Sci U S A. 1997 Sep 30;94(20):10979-84
9380745
Crit Care Med. 1996 Apr;24(4):672-8
8612421
J Comp Neurol. 1990 Sep 8;299(2):133-50
2172324
J Clin Neurophysiol. 2009 Aug;26(4):227-35
19584750
J Neurotrauma. 2008 Nov;25(11):1323-34
18976168