TNF and rheumatoid arthritis: Addorisio et al. demonstrated that vibrotactile stimulation administered to the cymba concha region of the outer ear could elicit vagal-mediated anti-inflammatory effects by reducing inflammatory markers in healthy adults (two studies: n = 6, decreased endotoxin induced TNF p < 0.01; n = 19, decreased TNF p < 0.05, IL-1β p < 0.001, and IL-6 p < 0.01) and lessening inflammatory responses in rheumatoid arthritis (RA) patients (n = 9, decreased DAS-28 score p < 0.05) [45].