Exploring the potential of a biophysical model to understand thermal sensation

This paper explores a biological perspective to understand thermal sensation. The main premise is that thermal sensation serves an organism for homeostasis of body temperature. A biological concept related to this premise is the thermoneutral zone (TNZ), which is defined as the range of operative temperatures where the body can maintain body core temperature without any regulatory changes to the metabolic rate or sweating. The centre of the TNZ can be regarded as the safest state for an animal from energetic and hydration perspective, as it provides most internal flexibility to cope with future thermal challenges. Therefore, we hypothesise that humans express neutral thermal sensation near the centre of their thermoneutral zone. To test this hypothesis, we define dTNZop as the distance between measured operative temperature and the centre of the TNZ. The TNZ centre was calculated with a biophysical model using measured data from a climate chamber study with 16 female subjects. Regression between observed thermal sensation votes (TSV) and dTNZop revealed that the intercept corresponds with a slightly higher than neutral TSV (0.14±0.07, p<0.001) and a strong linear relationship between TSV and dTNZop (R2=0.98). In conclusion, the approach shows great potential to improve our understanding of human thermal sensation.