The effects of laser acupuncture dosage at PC6 (Neiguan) on brain reactivity: a pilot resting-state fMRI study

Yi-Chuan Chang; Chun-Ming Chen; Ing-Shiow Lay; Yu-Chen Lee; Cheng-Hao Tu

doi:10.3389/fnins.2023.1264217

The effects of laser acupuncture dosage at PC6 (Neiguan) on brain reactivity: a pilot resting-state fMRI study

Front Neurosci. 2023 Oct 12:17:1264217. doi: 10.3389/fnins.2023.1264217. eCollection 2023.

Authors

Yi-Chuan Chang^{1

2}, Chun-Ming Chen³, Ing-Shiow Lay^{2

4}, Yu-Chen Lee^{1

5

6}, Cheng-Hao Tu¹

Affiliations

¹ Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan.
² Department of Chinese Medicine, China Medical University Beigang Hospital, Yunlin, Taiwan.
³ Department of Medical Imaging, China Medical University Hospital, Taichung, Taiwan.
⁴ School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan.
⁵ School of Chinese Medicine, China Medical University, Taichung, Taiwan.
⁶ Department of Chinese Medicine, China Medical University Hospital, Taichung, Taiwan.

Abstract

Previous studies indicated that laser acupuncture (LA) may effectively treat various medical conditions. However, brain responses associated with LA intervention have not been fully investigated. This study is focused on the effect of LA with different energy density (ED) in brain using resting-state functional magnetic resonance imaging (fMRI). We hypothesized that different ED would elicit various brain responses. We enrolled healthy adults participants and selected bilateral PC6 (Neiguan) as the intervention points. LA was applied, respectively, with ED of 0, 7.96, or 23.87 J/cm². Two 500-s resting-state fMRI scans were acquired before and after intervention, respectively. The functional connectivity (FC) was calculated between autonomic nerve system-regulation associated brainstem structures and other brain regions. Compared to other dosages, the FC between rostral ventrolateral medulla and orbitofrontal cortex has more enhanced; the FC between caudal ventrolateral medulla, nucleus of the solitary tract/nucleus ambiguus, and dorsal motor nucleus of the vagus and somatosensory area has more weakened when ED was 23.87 J/cm². Different dosages of LA have demonstrated varied regions of FC changes between regions of interest and other brain areas, which indicated that variations in EDs might influence the clinical efficacy and subsequent impacts through distinct neural pathways within the brain.

Keywords: Neiguan; functional connectivity; laser acupuncture; resting-state functional magnetic resonance imaging; rostral ventrolateral medulla.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by grants from National Science and Technology Council, Taiwan (NSC 111-2320-B-039-031-MY2) and the China Medical University, Taiwan (CMU 111-MF-45); Medical Research and Education Department, China Medical University Beigang Hospital (1-CMUBHR109-005). Details of all funding sources should be provided, including grant numbers if applicable. Please ensure to add all necessary funding information, as after publication this is no longer possible.