THERMAL PERCEPTUAL THRESHOLDS DEPEND ON ADAPTED SKIN TEMPERATURE IN MOUSE AND HUMAN

Sensory systems operate across a wide dynamic range of background signals and therefore, require adaptive mechanisms to maintain accurate and reliable sensitivity. However, in the thermal system, detection thresholds are not invariant. In humans, the threshold for warm detection decreases as the skin temperature increases, whereas it increases at lower skin temperatures. Conversely, thresholds for detecting cooling are lowest at low skin temperatures and increase as the skin temperature rises. Recent studies in mice have elucidated the neural circuits mediating thermosensation, but it remains unclear whether perceptual thresholds in mice depend on skin temperature and how these thresholds compare to those observed in humans. Here, we investigate how the adapted skin temperature influences the perceptual thresholds of non-painful thermal stimuli in both mice and humans using a comparable two-alternative forced-choice thermal detection task, where we deliver thermal stimuli to the mouse forepaw and to the human fingertip. We use an adaptive staircase procedure to estimate the psychometric curves for the detection of cooling and warming at four different adapted skin temperatures (20, 26, 32 and 38 degrees Celsius). This approach allows us to compare perceptual thresholds and sensitivities across species and thermal conditions. Preliminary results suggest that thermal thresholds vary systematically with skin temperature in a similar manner for both species. Together, these findings establish a framework for cross-species comparison of thermal perception and supports the translational relevance of mouse models for studying human thermosensation.