Perception of transient thermal environments: Pleasure and alliesthesia

Recent research indicates that dynamic thermal environments can potentially deliver higher levels of occupant satisfaction than static, homogenous indoor environments. The physiological concept of alliesthesia presents a coherent framework for investigating thermal pleasure arising from environmental or metabolic transients. This project investigated the relationship between core and skin temperatures and thermal pleasure in transient thermal environments. Pilot studies recorded skin temperature (Tsk) and core temperature (Tc) of six healthy males through a series of environmental and metabolic changes. Preliminary results indicate that sudden changes in ambient temperature were rated pleasantly whenever a positive alliesthesial effect was induced (i.e. opposite polarity of Tsk and Tc). This decayed as the subject returned to thermoneutrality. The same environmental step change invoked a displeasure response when the core temperature was stable. It is possible that higher levels of occupant satisfaction in transient or textured thermal environments may be explained by the hedonic overtones from the alliesthesial effect.