How does our sense of touch work?

Different receptors respond to different sensations. Meissner's corpuscles detect light touch, Merkel cells sense steady pressure and texture, Pacinian corpuscles pick up vibration and deep pressure, and Ruffini endings respond to skin stretching. Other nerve endings detect heat, cold and pain. Receptors are packed most densely in the fingertips, lips and tongue: on a fingertip you can tell two points apart when they are just a few millimetres apart, while on the back they may need to be several centimetres apart. Signals travel through the spinal cord to an area of the brain called the somatosensory cortex, where larger areas are devoted to the most sensitive body parts.