Functional MRI study on thalamus activation induced by electrical stimulation of different intensities.
- Author:
Yuan WANG
1
;
Ming ZHANG
;
Hai LIU
;
Shi-zheng ZHANG
;
Bo-lang YU
Author Information
1. Imaging Center, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an 710061,China.
- Publication Type:Journal Article
- MeSH:
Adult;
Electric Stimulation;
Female;
Humans;
Magnetic Resonance Imaging;
Male;
Pain;
physiopathology;
Pain Threshold;
Thalamus;
physiology
- From:
Journal of Central South University(Medical Sciences)
2008;33(1):26-30
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To detect the activation pattern of the thalamus in human by the functional magnetic resonance imaging (fMRI) with the electrical stimulation of different intensities, and to explore the mechanism of this area in pain modulation.
METHODS:Ten healthy right-handed volunteers were given different electrical stimulations of 1-, 2-, and 3- times pain threshold respectively. The whole-brain was scanned simultaneously by GE 1.5T magnetic resonance imaging system. The data were postprocessed by analysis of functional neuroimages (AFNI) to establish the regional activity maps of the thalamus.
RESULTS:Patterns of functional activity showed a positive linear relationship between the activation signals and stimulation intensity in bilateral thalamus, whereas the BOLD signal of bilateral medial thalamus demonstrated that the curve was similar to the exponential function. Meanwhile, the activation in the contralateral lateral thalamus (cThl), but not the contralateral medial thalamus (cThm), was prominent compared with the corresponding ipsilateral subregions, and only the lateral thalamus displayed a contralateral biased representation while the medial thalamus lacked this property.
CONCLUSION:Thalamus is one of the vital components in the pain modulation network, which can present spatial segregation activations with unique characteristics of stimulation intensity-response in each subregion. All the results are helpful to understand the crucial role of thalamus in processing the pain information.
