Effects of transcutaneous auricular vagus nerve stimulation on functional brain activity in patients with prolonged disorders of consciousness: A randomized controlled trial protocol using functional near-infrared spectroscopy and electroencephalography
10.1097/st9.0000000000000117
- Author:
Huan OUYANG
1
;
Yifei WANG
2
;
Ying HAN
2
;
Jinling ZHANG
2
;
Liang LI
2
;
Chen XIN
1
;
Jianghong HE
3
;
Peijing RONG
1
Author Information
1. Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
2. Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
3. Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- Publication Type:Journal Article
- Keywords:
Disorders of consciousness;
Electroencephalography;
Functional near-infrared spectroscopy;
Multidimensional;
Protocol;
Transcutaneous auricular vagus nerve stimulation
- From:
Science of Traditional Chinese Medicine
2026;4(2):181-187
- CountryChina
- Language:English
-
Abstract:
Background: Advances in intensive care have markedly improved survival after severe brain injury, leading to a growing population of patients with prolonged disorders of consciousness (pDOC). Current management of pDOC remains largely supportive, and evidence-based neuromodulatory interventions are limited; moreover, existing guidelines provide insufficiently explicit recommendations regarding mechanisms of action and objective biomarkers of treatment response. Transcutaneous auricular vagus nerve stimulation (taVNS) has emerged as a potential noninvasive intervention; however, its modulatory effects on brain function in pDOC are not yet well characterized, and the paucity of integrative mechanistic evidence has constrained its translation into routine clinical practice. Objectives: Within a multimodal assessment framework, this study aims to systematically elucidate the neurobiological mechanisms by which taVNS modulates brain function and autonomic activity in patients with pDOC, and to evaluate its clinical potential to enhance levels of consciousness. Methods: In this randomized controlled trial, 60 patients with vegetative state/minimally conscious state will be enrolled and randomly allocated to a taVNS group, a transcutaneous nonauricular vagus nerve stimulation group (sham), or a control group (n = 20 per group) for a 4-week intervention. The primary outcome will be changes in the Coma Recovery Scale-Revised scores from baseline to weeks 1, 2, and 4 of treatment. Secondary outcomes will include functional brain activity assessed by electroencephalography and functional near-infrared spectroscopy, as well as autonomic modulation indexed by heart rate variability. Functional prognosis will be evaluated using the Glasgow Outcome Scale-Extended at the end of treatment and at a 6-month follow-up. Safety will be assessed by continuous monitoring and documentation of adverse events throughout the study period. Results and discussion: By integrating electroencephalography–functional near-infrared spectroscopy with heart rate variability, this study will characterize the effects of taVNS on functional brain networks and consciousness recovery in pDOC across complementary behavioral, electrophysiological, hemodynamic, and autonomic domains, while interrogating potential sources of clinical and neurobiological heterogeneity. The findings are expected to provide a mechanistic and evidence-based foundation for the mechanism-driven clinical implementation of taVNS and the optimization of stimulation protocols in pDOC. Clinical trial registration: International Traditional Medicine Clinical Trial Registry, ITMCTR20250021041, https://itmctr.ccebtcm.org.cn.
