Efficacy and EEG-ECG mechanisms of taVNS combined with TEAS for negative symptoms of schizophrenia: a protocol for a 2 × 2 factorial randomized controlled trial
摘要
Negative symptoms of schizophrenia (NSS) represent a core feature of the disorder associated with substantial disease burden and poor functional prognosis, yet current therapeutic options remain limited. Given this unmet clinical need, we will explore the therapeutic potential of a combined non-pharmacological intervention using transcutaneous auricular vagus nerve stimulation (taVNS) and transcutaneous electrical acupoint stimulation (TEAS). In this single-blind, prospective, randomized controlled trial utilizing a 2 × 2 factorial design, 120 NSS participants will be randomly assigned in a 1:1:1:1 ratio to four groups: taVNS plus TEAS, taVNS plus sham TEAS, sham taVNS plus TEAS, and sham taVNS plus sham TEAS. Participants will receive 30-minute treatment sessions every other day for 4 weeks, with a subsequent 4-week follow-up period. The primary outcome is the reduction in the Positive and Negative Syndrome Scale-Factor Score for Negative Symptoms (PANSS-FSNS) at the end of the intervention at week 4 relative to baseline. This study aims to evaluate the individual and combined efficacy and safety of taVNS and TEAS in the treatment of NSS. Additionally, dual-modal synchronous electroencephalography (EEG) and electrocardiography (ECG) recordings will be used to investigate the neurophysiological mechanisms underlying the interventions and potential electrophysiological changes associated with the therapeutic effects. Trial registration: International Traditional Medicine Clinical Trial Registry (ITMCTR2025000634); registered on April 2, 2025.