FMRI connectivity analysis of acupuncture effects on an amygdala-associated brain network.
BACKGROUND
Recently, increasing evidence has indicated that the primary acupuncture effects are mediated by the central nervous system. However, specific brain networks underpinning these effects remain unclear.


RESULTS
In the present study using fMRI, we employed a within-condition interregional covariance analysis method to investigate functional connectivity of brain networks involved in acupuncture. The fMRI experiment was performed before, during and after acupuncture manipulations on healthy volunteers at an acupuncture point, which was previously implicated in a neural pathway for pain modulation. We first identified significant fMRI signal changes during acupuncture stimulation in the left amygdala, which was subsequently selected as a functional reference for connectivity analyses. Our results have demonstrated that there is a brain network associated with the amygdala during a resting condition. This network encompasses the brain structures that are implicated in both pain sensation and pain modulation. We also found that such a pain-related network could be modulated by both verum acupuncture and sham acupuncture. Furthermore, compared with a sham acupuncture, the verum acupuncture induced a higher level of correlations among the amygdala-associated network.


CONCLUSIONS
Our findings indicate that acupuncture may change this amygdala-specific brain network into a functional state that underlies pain perception and pain modulation.
Qin
Wei
W
Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, Beijing, PR China. wei.qin@ia.ac.cn
Tian
Jie
J
Bai
Lijun
L
Pan
Xiaohong
X
Yang
Lin
L
Chen
Peng
P
Dai
Jianping
J
Ai
Lin
L
Zhao
Baixiao
B
Gong
Qiyong
Q
Wang
Wei
W
von Deneen
Karen M
KM
Liu
Yijun
Y
D015670:Acupuncture Therapy; D000679:Amygdala / Q000502:physiology*; D001931:Brain Mapping; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009434:Neural Pathways; D010146:Pain / Q000503:physiopathology*