Spatial summation of cold.
D001415:Back / Q000502:physiology; D002610:Cheek / Q000502:physiology; D003080:Cold Temperature; D005542:Forearm / Q000502:physiology; D006801:Humans; D012867:Skin / Q000098:blood supply; D012879:Skin Physiological Phenomena; D012881:Skin Temperature; D013697:Thermosensing / Q000502:physiology*; D014661:Vasoconstriction