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Updated: Jun 11, 2025

Using Facial Electromyography to Assess Facial Muscle Reactions to Experienced and Observed Affective Touch in Humans
Published on: March 15, 2019
Number of Facial Hair Corresponds to Frequency of Spontaneous Face-Touch in Humans
Martin Grunwald1, Welda P M Pasatu1, Jente Spille1
1Paul Flechsig Institute - Centre of Neuropathology and Brain Research, Haptic Research Laboratory, University of Leipzig, 04103, Leipzig, Germany.
Abstract:
People all over the world, independent of their culture or background, touch their faces up to 800 times per day. No other part of the body is touched as often as the face. Forehead, nose, and chin-the so-called T-zone of the face-are touched particularly frequently during spontaneous facial self-touches (sFST). It is hypothesized that there is a relationship between the density of mechanoreceptors (inferred from facial hair distribution) and the frequency of spontaneous self-touching. In order to indirectly measure the density of mechanoreceptors (cutaneous end organ complexes), the number of vellus and terminal hairs at 40 different measuring points on the face of 30 (15f/15m) healthy volunteers in study A is determined. In study B, the frequency of sFST at the same 40 measuring points in 66 (32f/34m) healthy persons is determined. Study A reveals that the number of facial hairs-in both sexes-is higher in the T-zone than in other areas of the face. Study B reveals that the T-zone is touched more frequently than other areas of the face. Skin areas of the face with a higher number of vellus hairs (and presumably higher innervation density) are touched particularly frequently during sFST.
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