''Social touch is capable of stimulating the body’s natural painkillers, while warm physical contact among couples can lead to decreases in blood pressure"
When puppies are separated from their mothers, the loss of touch inhibits secretion of growth hormones and DNA synthesis, and stimulates excessive stress responses. Importantly, these effects can be selectively reversed by soft, gentle stroking of the puppy, but not by other types of stimulation.
It has also been proved in humans that social touch is a very good medicine for stress and pain of many kinds, as it is capable of stimulating the body’s natural painkillers. Simple, everyday behaviours, such as hand-holding with partners, family members or friends, are capable of regulating both mental and physical stress and pain.
Several investigations in adults have found that warm, social, physical contact among couples can lead to decreases in blood pressure and stress, and can reduce physical pain.
Similar findings are piling up regarding the role of hugs, massage and other touch-based ways to influence the neurochemistry of the brain associated with stress, pain and bonding.
The effect of touch on the brain
Most theories link the effects of touch with three neurochemical systems in the brain – the cortisol-based stress-reactivity system, ‘social’ hormones such as oxytocin (the feel-good hormone sometimes known as the love drug) and the opioid system. Work in other animals has confirmed the importance of touch in these and other neurochemical systems.
Affiliative touch behaviours, such as grooming, tactile play and tickling, have been shown to stimulate the production of the body’s natural opiates, the endorphins, so that, for example, the more grooming a monkey receives, the greater the changes in the brain’s opioid system.
There are also similar findings in animals as regards the flow of oxytocin, known to be released during orgasm. What these neurochemical systems seem to have in common, other than their tight links with touch and social bonding, is their association with sensory pleasure and analgesic effects.
There’s no doubt that positive touch has a unique evolutionary role in linking us to other members of our species and regulating our health in the process.