The ability to feel our surroundings is one of the first senses humans developed. Unlike the other four classic senses, touch is multifaceted and is perceived as a result of multisense systems within the skin. However, when we talk about everyday touch we are referring to something called haptic touch. Embedded in the skin are an array of nerve cells called mechanosensory neurons, whose job is to let the brain know information about objects the skin comes into contact with. For example, nerve receptors called Pacinian corpuscles detect changes in pressure, whereas Ruffini corpuscles detect warmth. These nerve receptors then send electrical signals through the nervous system and along the spinal cord to the brain for interpretation. Under the umbrella of ‘touch’ is another type of sense called nociception. You might not have heard the term, but you’ll be painfully aware of its existence. Nociception is the body’s ability to recognise pain, and the nervous system communicates with the brain to react accordingly. For example, pricking your finger or stubbing your toe triggers pain receptors, found in the majority of bodily tissue, that raise the alarm bells in the brain via nerve cells travelling up the spinal cord. The brain then returns the signal through the nervous system to coordinate a response, such as contracting muscle to recoil limbs or releasing natural painkillers into the bloodstream.
SUPER SENSE