Tension-type headache patients' brain responses to instant acupuncture stimulation: a functional magnetic resonance imaging study.

OBJECTIVES

To investigate the effects of instant acupuncture stimulation on brain activity in patients with tension-type headache (TTH) compared to healthy controls (HCs).

METHODS

Thirty-six TTH patients and thirty-six HCs participated in this study. Both groups underwent resting-state and acupuncture-state functional magnetic resonance imaging (fMRI) scans. The amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and regional homogeneity (ReHo) were used to assess spontaneous brain activity of participants. Additionally, participants' acupuncture sensation scores during stimulation were recorded, and brain activity differences between TTH patients and HCs with similar sensations (with predominately Deqi sensation or acute pain) were compared. This study was officially registered on the Chinese Clinical Trial Registry (ChiCTR) as a sub-study of the parent clinical trial (No. ChiCTR2100042915).

RESULTS

Both groups showed activation in the superior frontal gyrus, supramarginal gyrus, and precuneus, along with deactivation in the precentral/postcentral gyrus, inferior occipital gyrus, lingual gyrus, and superior temporal gyrus during acupuncture stimulation. Notably, TTH patients also exhibited increased activity in the anterior cingulate cortex and caudate nucleus, as well as decreased activity in the parietal operculum. TTH patients and HCs with acute pain sensations demonstrated similar spontaneous functional brain activity in the precentral/postcentral gyrus, lingual gyrus, and cuneus/precuneus. Furthermore, HCs with pronounced Deqi sensations exhibited functional changes in the precentral/postcentral gyrus, whereas no such changes were observed in the TTH patients.

CONCLUSION

The modification of functional activity in the sensorimotor system, default mode network (DMN), and visual network (VN) during acupuncture stimulation suggest common brain responses in both TTH patients and HCs. In addition, acupuncture at Siguan acupoints could extensively regulate the limbic system in TTH patients, and showed targeted modulation in the abnormal brain regions of the ACC and caudate nucleus, which are closely related to the regulation of pain emotions and cognition.

CLINICAL TRIAL REGISTRATION: This study was officially registered on the Chinese Clinical Trial Registry (ChiCTR, https://www.chictr.org.cn/) as a sub-study of the parent clinical trial (No. ChiCTR2100042915).