Cold and warmth perception mapped for age, gender, and body area.

Reference data on cold and warmth perception at three different body areas are provided based on 24 young (20-30 years) and 24 elderly (55-65 years) healthy women and men. Perception thresholds (method of limits), perceived intensity (free-number magnitude estimation), and perceived quality (verbal descriptors) were assessed for cold and for warmth at thenar, the upper arm, the knee, and the foot. Inter-individual comparison of perceived-intensity scales for cold and warmth was achieved by a Master Scaling procedure utilizing thenar as a reference area. Perception thresholds showed gender difference for cold at thenar, and interaction effect of age and gender for heat-pain tolerance at the upper arm. In contrast, perceived intensity of cold and warmth showed multiple effects of age, gender, and specific body area (also for the nociceptive channels). For instance, at the knee, elderly women's perceived intensity for stimulation in the nociceptive range was elevated for both cold and warmth, as compared to young women and men, and to elderly men. Conversely, at the upper arm, elderly women's perceived intensity for the corresponding nociceptive range was lowered, as compared to young women and young men, and to elderly men. At the foot, both elderly women's and men's perceived intensity of cold and warmth was lowered, as compared to young women and men. Overall, the perceived quality of perceptions did not differ between groups. The present findings on age differences in perceived intensity of cold and warmth at the upper arm, knee and foot in healthy women and men provide reference data hitherto lacking for diagnostic work in patients with somatosensory dysfunctions and ongoing pain.