Acupuncture induces divergent alterations of functional connectivity within conventional frequency bands: evidence from MEG recordings

Youbo You; Lijun Bai; Ruwei Dai; Chongguang Zhong; Ting Xue; Hu Wang; Zhenyu Liu; Wenjuan Wei; Jie Tian

doi:10.1371/journal.pone.0049250

Acupuncture induces divergent alterations of functional connectivity within conventional frequency bands: evidence from MEG recordings

PLoS One. 2012;7(11):e49250. doi: 10.1371/journal.pone.0049250. Epub 2012 Nov 9.

Authors

Youbo You¹, Lijun Bai, Ruwei Dai, Chongguang Zhong, Ting Xue, Hu Wang, Zhenyu Liu, Wenjuan Wei, Jie Tian

Affiliation

¹ Intelligent Medical Research Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China.

Abstract

As an ancient Chinese healing modality which has gained increasing popularity in modern society, acupuncture involves stimulation with fine needles inserted into acupoints. Both traditional literature and clinical data indicated that modulation effects largely depend on specific designated acupoints. However, scientific representations of acupoint specificity remain controversial. In the present study, considering the new findings on the sustained effects of acupuncture and its time-varied temporal characteristics, we employed an electrophysiological imaging modality namely magnetoencephalography with a temporal resolution on the order of milliseconds. Taken into account the differential band-limited signal modulations induced by acupuncture, we sought to explore whether or not stimulation at Stomach Meridian 36 (ST36) and a nearby non-meridian point (NAP) would evoke divergent functional connectivity alterations within delta, theta, alpha, beta and gamma bands. Whole-head scanning was performed on 28 healthy participants during an eyes-closed no-task condition both preceding and following acupuncture. Data analysis involved calculation of band-limited power (BLP) followed by pair-wise BLP correlations. Further averaging was conducted to obtain local and remote connectivity. Statistical analyses revealed the increased connection degree of the left temporal cortex within delta (0.5-4 Hz), beta (13-30 Hz) and gamma (30-48 Hz) bands following verum acupuncture. Moreover, we not only validated the closer linkage of the left temporal cortex with the prefrontal and frontal cortices, but further pinpointed that such patterns were more extensively distributed in the ST36 group in the delta and beta bands compared to the restriction only to the delta band for NAP. Psychophysical results for significant pain threshold elevation further confirmed the analgesic effect of acupuncture at ST36. In conclusion, our findings may provide a new perspective to lend support for the specificity of neural expression underlying acupuncture.

Publication types

Clinical Trial
Research Support, Non-U.S. Gov't

MeSH terms

Acupuncture Therapy*
Adult
Female
Humans
Magnetoencephalography / methods*
Male
Meridians
Nerve Net / physiology*

Grants and funding

This paper is supported by the Knowledge Innovation Program of the Chinese Academy of Sciences under Grant No. KGCX2-YW-129, the National Natural Science Foundation of China under Grant Nos. 30873462, 30970769, 30970771, 60910006, 81071217, 81171314, the Joint Research Fund for Overseas Chinese Scholars and Scholars in Hong Kong and Macao funder Grant No. 31028010, the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists under Grant No. 2010T2G36, the Fundamental Research Funds for the Central University, Beijing Nova program under Grant No. Z111101054511116, and the National Basic Research Program of China (973 Program) under Grant No. 2011CB707700. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.