title: Divergent neural processes specific to the acute and sustained phases of verum and SHAM acupuncture.
abstract: OBJECTIVE
  To discuss which brain region potentially functioned and switched between the immediate and delayed response of acupuncture.
  
  
  METHODS
  A nonrepeated event-related functional MRI (fMRI) design was used to investigate the spatial and temporal patterns of acupuncture effects induced by needling an acupoint ST36 (ACU) and a nonmeridian point (SHAM). The standard general linear model was used to detect the immediate neural responses of acupuncture. Graph theory analysis was used to characterize the functional integrated network of the acupuncture delayed effect.
  
  
  RESULTS
  Acupuncture induced significant signal changes in the limbic/paralimbic areas, neocortical regions, brainstem, and cerebellum for immediate effect both in ACU and SHAM. Some of these brain regions showed strong functional connectivity for a delayed effect in ACU. Conjunction analysis showed that the insula played a critical role during the overall process of ACU. No overlapping brain regions were found in SHAM.
  
  
  CONCLUSIONS
  The findings of this study suggested that the delayed effects may reflect a more significant characteristic underlying acupuncture. Given that the insula as a relay station switched between the immediate and delayed response, it suggested that divergent functional connectivity patterns may mediate the acupuncture-related effects for ACU and SHAM.
authors.affiliation: Life Sciences Research Center, School of Life Sciences and Technology, Xidian University, Xi'an, Shaanxi, China.
authors.forename: Jixin
authors.initials: J
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Qin
authors.forename: Qian
authors.initials: Q
authors.lastname: Guo
authors.forename: Jinbo
authors.initials: J
authors.lastname: Sun
authors.forename: Kai
authors.initials: K
authors.lastname: Yuan
authors.forename: Minghao
authors.initials: M
authors.lastname: Dong
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Karen M
authors.initials: KM
authors.lastname: von Deneen
authors.forename: Yijun
authors.initials: Y
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Tian
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy / Q000379:methods*; D001931:Brain Mapping / Q000379:methods; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D010812:Physical Stimulation / Q000379:methods*; D012677:Sensation / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*; D055815:Young Adult