Effect of Isometric Muscle Contraction on the Somatosensory Evoked Potentials.
- Author:
Min Kyun SOHN
1
;
Young Kyoung KIM
;
Jeong Young SONG
;
Soo Kyoung BOK
;
Kang Hee CHO
;
Bong Ok KIM
Author Information
1. Department of Rehabilitation Medicine, Chungnam National University College of Medicine.
- Publication Type:Original Article
- Keywords:
Isometric muscle contraction;
Somatosensory evoked potentials;
Gating
- MeSH:
Adult;
Central Nervous System;
Evoked Potentials, Somatosensory*;
Humans;
Isometric Contraction;
Median Nerve;
Muscle Contraction*;
Muscles;
Peripheral Nervous System;
Relaxation;
Scalp
- From:Journal of the Korean Academy of Rehabilitation Medicine
2001;25(1):85-90
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVE: To investigate the association of the muscle contraction with gating of the sensory input at central and peripheral levels according to the intensity of muscle contraction and location of the muscles, somatosensory evoked potentials (SSEPs) studies were evaluated at different levels of isometric contraction in the different muscles. METHOD: Median nerve SSEPs were recorded at Erb's point and scalp in the ten healthy adult subjects with isometric contraction of ipsilateral abductor pollicis brevis (APB), ipsilateral abductor digiti minimi (ADM) and contralateral APB. Median nerve SSEPs were recorded in each of these conditions during precontraction, weak contraction, strong contraction and 4 minutes after contraction. RESULTS: 1) N9 amplitudes of median SSEPs recorded at Erb's point were augumented during weak contraction and these amplitude augumentations were statistically significant in the ipsilateral APB contraction (p<0.05). 2) N20 amplitudes recorded at scalp were inhibited during strong isometric contraction and these amplitude inhibitions were statistically significant in the ipsilateral APB contraction (p<0.05). 3) The latencies of N9 and N20 potentials were not significantly changed during isometric contraction. CONCLUSION: Therefore peripheral nervous system as well as central nervous system is responsible for gating, so the subject should be asked for the best relaxation possible for higher reliability of SSEPs.