A recent study conducted at Hangzhou Armed Police Hospital in China investigated the potential of transcutaneous auricular vagus nerve stimulation (taVNS) in diagnosing disorders of consciousness (DoC) following severe brain injuries. The research, which ran from February 2022 to February 2024, involved 36 DoC patients (17 Minimally Conscious State (MCS), 19 Unresponsive Wakefulness Syndrome (UWS)) and 26 healthy controls. Researchers administered taVNS for ten minutes while monitoring heart rate variability (HRV) via electrocardiogram (ECG).
The study found significant differences in HRV parameters between healthy individuals and DoC patients, as well as between MCS and UWS patients. Support Vector Machine (SVM) modeling, using HRV features, accurately classified healthy controls versus DoC patients with 86% accuracy and MCS versus UWS patients with 78% accuracy. Furthermore, the SVM model predicted patient outcomes three months post-intervention with 86% accuracy and confirmed these predictions at six months with 71% accuracy.
These findings suggest that taVNS, by modulating autonomic responses, could serve as a valuable tool in diagnosing and potentially treating DoC. The study highlights the importance of brain-heart dynamics in understanding and addressing these complex neurological conditions.