Scientists now know the mechanism behind the sensation of touch. It starts with something called Merkel Cells, also known as Tactile Cells.

These epithelial Tactile Cells have the ability to receive light touch signals and to discern shape and texture. They help us know the quality, grain, and consistency of a surface. Even more interestingly, they “interact with neurons to enable us to recognize sensitive touch.” That means they allow us to experience touching not just objects, but also each other.

Cradling

We already know some valuable information about the science of touch. For instance, if a mother is holding a newborn, “the emotional impact of touch is more direct and immediate if an infant is held to the left side of the body (‘left-sided cradling’).” Clinicians assess the quality and amount of affectionate interpersonal touch between mother and child by watching maternal eye gaze, cooing, cuddling, and cradling. In fact, they have begun to pay attention when they see an excessive amount of right-sided cradling because it “…has been associated with maternal depression and maternal stress,” and the findings show that “…adults who cradle on the right are more detached and less responsive to their infants than those who cradle on the left.”

Keep in mind, this doesn’t mean you should never shift shoulders or switch sides while breast-feeding. Balance is fine. Movement is good. Engagement makes the most difference. During all physical and emotional interaction, the infant is gathering information, and the brain processes that information.

As a securely attached infant moves toward toddler-hood, he or she integrates what has been learned about sight, sound, and touch in such a way that a sense of self-hood can emerge.

Hugging

British psychologist Emese Nagy studied athletes and their embraces, discovering that most people hug for an average of three seconds. Those three seconds sometimes extended to four or five seconds, if the athletes were more supportive than competitive.

In our relationships with friends and colleagues, a three second hug is the norm. But science indicates that it takes much longer to get the true benefit from a hug. Once the hug lasts a full 20 seconds, oxytocin is released. Oxytocin is a bonding hormone that creates intimacy, lowers inflammation, reduces anxiety, and increases contentment.

If you want a dose of oxytocin, you’re better off hugging someone you genuinely feel close to, rather than any random stranger or a co-worker or boss. Save your best hugs for the people you love best, and the oxytocin will do its work for you.

Kissing

Researchers agree that kissing reduces cortisol levels. Cortisol is a stress hormone, which becomes elevated during times of stress and depression. Kissing, therefore, is thought to improve mood and reduce anxiety.

John Gottman, researcher and expert therapist, encourages couples to remember to kiss each other goodbye when they are parting. He suggests avoiding quick pecks and opting instead for the six-second kiss. This indicates a willingness to devote time to the relationship, solidifies bonding and improves intimacy in marriage. Marriage workshops often teach couples the art of the six-second kiss as a way to reconnect.

The best kind of touch

The consensus is that light touch is most pleasant. Slow, loving strokes are thought to be the most beneficial kind of touch. Coach Christopher Bergland explains, “Researchers in the UK found that loving touch, characterized by a slow caress or gentle stroking increases the brain’s ability to construct a sense of body ownership and plays a big part in creating and sustaining a healthy sense of self.”

Much of the research indicates that light touch is most restorative and hormonally beneficial. Studies even show that it creates a greater likelihood that a person will receive help when asked, or offer compliance when requested, or tip a server more generously.

A word of caution about light touch

Some of us, however, have Tactile Cells that receive information differently. That difference is called Tactile Defensiveness. One person explained it like this: “The general theory of tactile defensiveness is that the light touch receptors in the skin are overly sensitive, triggering a ‘fight or flight’ response, that causes the sufferer to perceive certain types of touch as threatening.” The result is that a well-meaning spouse might lightly caress his partner on the back and be met not with gratitude, but with irritation, fear, or even anger.

Evidence points to the idea that many individuals on the autism spectrum cannot bear light touch. There are whole websites devoted to the topic, and long conversational feeds full of people who hate light touch. Yes, many of these people identify as being on the autism spectrum, but not all. I know at least four people (and I’m one of them) who are not on the spectrum and still experience tactile defensiveness. It can take time to teach loved ones to touch in the way that feels most comfortable to the person being touched.

Conclusion

Relationships, especially close ones, typically involve some level of touch. We can rewire the way we give and receive touch by paying attention to the quality of touch, the duration, and the particular preferences of the people in our lives.