Researchers found that cold is detected differently in the skin than in internal organs. This split system helps explain why cold air, cold drinks, and cold surfaces create vrey different sensations.
A research group led by Félix Viana, co-director of the Sensory Transduction and Nociception laboratory at the Institute for Neurosciences (IN), has found that the body does not rely on a single method to detect cold. Instead, the skin and internal organs use distinct molecular mechanisms to sense temperature changes. The Institute for Neurosciences (IN) is a joint research center of the Spanish National Research Council (CSIC) and Miguel Hernández University of Elche (UMH). This revelation advances scientists’ understanding of thermal homeostasis and sheds light on medical conditions linked to abnormal sensitivity to cold.
The results were recently published in the journal *Acta Physiologica*. They show that cold perception varies depending on the tissue involved. In the skin, low temperatures are mainly detected by an ion channel called TRPM8, which is especially suited to sensing cool environmental conditions. Internal organs, including the lungs and stomach, depend instead on a different molecular sensor known as TRPA1 to register drops in temperature.
Why Cold Feels Different Inside the Body
These separate sensing systems help explain why cold on the skin feels unlike the sensation of breathing icy air or swallowing a very cold drink. Different tissues activate different biological pathways to detect temperature changes. As Félix Viana explains, “The skin is equipped with specific sensors that allow us to detect environmental cold and adapt defensive behaviors.” He adds: “in contrast, cold detection inside the body appears to depend on different sensory circuits and molecular receptors, reflecting its deeper physiological role in internal regulation and responses to environmental stimuli.”
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