The Effects of Acupuncture at Shuigou (GV26) on Patients With Disorders of Consciousness: An EEG Nonlinear Dynamics Analysis

Background Disorders of consciousness (DOC) lack objective biomarkers. We evaluated the immediate cortical effects of acupuncture at Shuigou (GV26) in DOC patients using nonlinear EEG parameters: approximate entropy (ApEn), Lempel–Ziv complexity (LZC), correlation dimension ( D 2 ), and cross-approximate entropy (C-ApEn). Methods In a prospective study, 32 DOC patients (vegetative state/unresponsive wakefulness syndrome [VS/UWS], n = 17; MCS, n = 15) received 260-s manual acupuncture at GV26. Resting-state EEG was recorded pre- and postintervention. Nonlinear parameters were computed across 19 electrodes and compared between groups using independent/paired tests. Correlations with Coma Recovery Scale-Revised (CRS-R) scores were assessed via Spearman's analysis. Results Baseline ApEn, D 2 , and LZC were higher in minimally conscious state (MCS) than VS/UWS ( P < 0.05). Postacupuncture, ApEn increased in frontal, central, occipital (VS/UWS) and prefrontal, central, occipital, and temporal (MCS) regions ( P < 0.05). D 2 increased in all regions (VS/UWS) and occipital/temporal regions (MCS) ( P < 0.05). C-ApEn revealed enhanced connectivity, especially in VS/UWS. LZC showed no significant change. All parameters correlated positively with CRS-R; D 2 exhibited the strongest association ( r = 565–0.592, P < 0.01). Conclusion Acupuncture at GV26 acutely modulates cortical complexity and connectivity in DOC. D 2 and ApEn emerge as potentially sensitive markers of consciousness level and therapeutic response. Nonlinear EEG analysis offers a promising objective tool for evaluating neuromodulation in DOC.