The neural circuitry that underlies the perception of skin cooling is unclear. To examine this, the authors trained mice to report temperature drops (delivered by a thermal probe applied to the forepaw skin) by licking a water dispenser. Cooling induced activity in the primary somatosensory cortex (S1). Moreover, mice lacking the cold-responsive ion channel TRPM8, which is expressed in sensory afferents that innervate the skin, did not show cooling-induced licking or S1 activation. Thus, TRPM8-expressing sensory neurons and S1 cortical neurons form parts of a cooling perception circuit in mice.