Clinical trials of the cVES Vagus Nerve device were carried out in 2019 and 2020 at the Korea Research Institute of Standards and Science in South Korea. These trials used EEG (electroencephalogram) to measure Alpha brain wave power, and ECG (Electrocardiogram) to measure normalized spectral heart rate variability (HRV). HRV low-frequency (HRV-LF) oscillation represents vasomotor activity, which indicates activity and stress. High-frequency (HRV-HF) oscillation corresponds to respiratory activity, which represents relaxation and reflects parasympathetic nervous system activity.
In both these trials, patients wearing the cVES device showed a significant increase of alpha wave ratios, indicating a reduction in stress. There were also significant increases in HRV-HF measured 2-hours, 1-day, 2-days and 3-days after using the device. This demonstrated that the device not only has short term effects, but also provides long term effects in activating the parasympathetic nervous system.