title: Tactile cues significantly modulate the perception of sweat-induced skin wetness independently of the level of physical skin wetness.
abstract: Humans sense the wetness of a wet surface through the somatosensory integration of thermal and tactile inputs generated by the interaction between skin and moisture. However, little is known on how wetness is sensed when moisture is produced via sweating. We tested the hypothesis that, in the absence of skin cooling, intermittent tactile cues, as coded by low-threshold skin mechanoreceptors, modulate the perception of sweat-induced skin wetness, independently of the level of physical wetness. Ten males (22 yr old) performed an incremental exercise protocol during two trials designed to induce the same physical skin wetness but to induce lower (TIGHT-FIT) and higher (LOOSE-FIT) wetness perception. In the TIGHT-FIT, a tight-fitting clothing ensemble limited intermittent skin-sweat-clothing tactile interactions. In the LOOSE-FIT, a loose-fitting ensemble allowed free skin-sweat-clothing interactions. Heart rate, core and skin temperature, galvanic skin conductance (GSC), and physical (w(body)) and perceived skin wetness were recorded. Exercise-induced sweat production and physical wetness increased significantly [GSC: 3.1 μS, SD 0.3 to 18.8 μS, SD 1.3, P < 0.01; w(body): 0.26 no-dimension units (nd), SD 0.02, to 0.92 nd, SD 0.01, P < 0.01], with no differences between TIGHT-FIT and LOOSE-FIT (P > 0.05). However, the limited intermittent tactile inputs generated by the TIGHT-FIT ensemble reduced significantly whole-body and regional wetness perception (P < 0.01). This reduction was more pronounced when between 40 and 80% of the body was covered in sweat. We conclude that the central integration of intermittent mechanical interactions between skin, sweat, and clothing, as coded by low-threshold skin mechanoreceptors, significantly contributes to the ability to sense sweat-induced skin wetness.
authors: Environmental Ergonomics Research Centre, Loughborough Design School, Loughborough University, Loughborough, United Kingdom; davidefilingeri@hotmail.it.
authors: Davide
authors: D
authors: Filingeri
authors: Thermal Sciences Laboratory, Oxylane Research, Villeneuve d'Ascq, France.
authors: Damien
authors: D
authors: Fournet
authors: Environmental Ergonomics Research Centre, Loughborough Design School, Loughborough University, Loughborough, United Kingdom;
authors: Simon
authors: S
authors: Hodder
authors: Environmental Ergonomics Research Centre, Loughborough Design School, Loughborough University, Loughborough, United Kingdom;
authors: George
authors: G
authors: Havenith
mesh_terms: D015992:Body Mass Index; D003020:Clothing; D003463:Cues; D015444:Exercise; D005712:Galvanic Skin Response / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010812:Physical Stimulation; D011601:Psychophysics; D012044:Regression Analysis; D012867:Skin / Q000294:innervation*; D012881:Skin Temperature / Q000502:physiology*; D013697:Thermosensing / Q000502:physiology*; D013997:Time Factors; D014110:Touch / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*; D055815:Young Adult
keywords: mechanoreceptors; skin; sweating; tactile; wetness