High resolution topographical mapping of warm and cold sensitivities

ObjectiveThis study aims to explore the thermal sensitivity distribution (topographical mapping) over the glabrous skin of the hand in males and females.MethodsWarm (WT) and cold (CT) thresholds were measured in 25 healthy volunteers (12 females), applying a multi-site test of 23 locations on the volar part of the hand.ResultsThe palm area was more sensitive than the fingers to both warm (P < 0.001) and cold (P < 0.001) stimuli. On the palm itself, the proximal part was the most sensitive (P < 0.05). Heterogeneity was also found to both warm and cold sensibilities within dermatomes (P < 0.05) as well as to cold sensitivity across dermatomes (P < 0.001). Females were more sensitive than males to both warm (P < 0.001) and cold sensations (P < 0.001). In addition, painful components were frequently reported as accompanying warm/cold sensations during mild warming/cooling.ConclusionsThe thermal sensitivity distribution over the glabrous skin of the hand is highly heterogeneous.SignificanceIt is appropriate to precisely define testing locations when conducting thermal examinations on the hand.