Objective
To explore the effects of tactile stimulation using air pressure at the auricular branch of the vagus nerve on autonomic activity in healthy individuals.
Methods
Three types of tactile stimulation were used in this study: continuous low-amplitude, continuous high-amplitude, and pulsed airflow. The tactile stimulations were provided to the cymba concha to investigate autonomic activity in 22 healthy participants. The mean heart rate (HR) and parameters of HR variability, including the standard deviation of R-R intervals (SDNN) and root mean square of successive R-R interval differences (RMSSD) were compared at baseline, stimulation, and recovery periods.
Results
Two-way repeated measures ANOVA indicated a significant main effect of time on HR (p=0.001), SDNN (p=0.003), and RMSSD (p<0.001). These parameters showed significant differences between baseline and stimulation periods and baseline and recovery periods in the post-hoc analyses. There were no significant differences in the changes induced by stimulation type and the interaction between time and stimulation type for all parameters. One-way repeated measures ANOVA showed that HR, SDNN, and RMSSD did not differ significantly among the three time periods during sham stimulation.
Conclusion
Parasympathetic activity can be enhanced by auricular tactile stimulation using air pressure, targeting the cymba concha. Further studies are warranted to investigate the optimal stimulation parameters for potential clinical significance.

Citations

• Effects of tactile auricular vagus nerve stimulation using heated and humidified airflow on cardiac autonomic activity: a pilot experimental study
  Soohyun Wi, Sungwoo Park, Byung-Mo Oh, Han Gil Seo, Yae Lim Lee, Woo Hyung Lee
  Clinical Autonomic Research.2025; 35(3): 519.     CrossRef
• Auricular neuromodulation may act through interoception modulation
  Frédéric Canini, Damien Claverie, Florence Weill, Christine Pailler, Béatrice Paquier, Mireille Michel-Cherqui, Sonia Pellissier, Marion Trousselard, Emmanuel Sagui
  Brain Research.2025; 1863: 149736.     CrossRef
• Stroking Stimuli to the Ear to Enhance Pleasant and Non-arousing Feelings while Listening to Sounds
  Yuta GOTO, Shogo OKAMOTO
  International Journal of Affective Engineering.2024; 23(3): 251.     CrossRef
• Relaxation Effects of Auricular Vibration Stimuli Synchronized with Music
  Yuta GOTO, Shogo OKAMOTO
  International Symposium on Affective Science and Engineering.2024; ISASE2024: 1.     CrossRef