Touch is the sense that detects pressure, temperature, vibration, and pain through receptors in the skin and deeper tissues. It is essential for manipulating objects, avoiding injury, and maintaining social connection.

Different receptor types respond to different features: Meissner’s corpuscles and Merkel cells to light touch, Pacinian corpuscles to vibration, free nerve endings to temperature and pain. Signals travel via the spinal cord to the thalamus and then to the somatosensory cortex, where a map of the body surface is maintained. The density of receptors varies dramatically; the fingertips and lips are far more sensitive than the back.

Touch is not a single sense but a family of related channels. Affective touch, mediated by specialized fibers, contributes to the emotional quality of social contact. Pain, while often grouped with touch, has its own pathways and can be modulated by attention, expectation, and descending control from the brain. Loss of touch sensation severely impairs dexterity and safety.

The skin’s continuous report of contact with the world is the sense of touch.