Ameliorating Effects and Mechanisms of TaVNS on Constipation in PD Patients.

Transcutaneous auricular vagus nerve stimulation was conducted by transcutaneous electrical stimulation therapy instrument to the cymba conchae of left ear in the vicinity of the auricular branch vagus nerve. Stimulation parameters: frequency = 20 Hz; pulse width = 500 μs, twice a day, 30 minutes each time.

In the sham stimulation group, the electrodes were fixed at the left earlobe with the same stimulus parameters. Stimulation parameters: frequency = 20 Hz; pulse width = 500 μs, twice a day, 30 minutes each time.