Background
The somatosensory system processes information on stimuli to the body and plays an important role in sensation and recognition. In addition, somatosensory stimuli elicit various physiological responses, such as motor functions, autonomic functions, and hormonal secretions [To imitate continuous skin touch with a fingertip, stimulation discs, which have fine brushes called “microcones”, have been developed as inspired by non-penetrating, contact acupuncture, i.e., Japanese pediatric acupuncture [Chronic neck and shoulder discomfort is one of the most common symptoms, and the prevalence in the Japanese population is reportedly 8.7% according to the National Survey of Basic Living Conditions in 2019 [This study aimed to investigate the efficacy of a 2-week self-administered gentle mechanical skin stimulation with microcones on subjective and objective symptoms of chronic neck and shoulder discomfort. As objective symptoms, range of motions (ROMs) of the neck and shoulder regions, which are known to be decreased in people with chronic neck and shoulder discomfort [