High resolution topographical mapping of warm and cold sensitivities

Objective: This study aims to explore the thermal sensitivity distribution (topographical mapping) over the glabrous skin of the hand in males and females. Methods: Warm (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. Results: The 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. Conclusions: The thermal sensitivity distribution over the glabrous skin of the hand is highly heterogeneous. Significance: It is appropriate to precisely define testing locations when conducting thermal examinations on the hand.