With a Gentle Touch
New research shows the changing importance of gentle touching as we grow older.
Posted Mar 30, 2016
“See how she leans her cheek upon her hand. O, that I were a glove upon that hand
That I might touch that cheek!” William Shakespeare
The physical sensation of being touched can have a powerful effect depending on the way you are being touched and who is doing the touching.
Whether you are being gently stroked by a significant other or receiving an affectionate touch from a friend or family member, the pleasure that touch brings is an important part of most social relationships. Even in professional settings, a pleasant handshake helps reinforce the close association we often have with employers and co-workers. Touch can also be important in health care settings with worried patients often feeling reassured by the friendly touch of a doctor or nurse.
The sensation of being touched can produce a wide range of physiological and biochemical changes in the body including decreased heart rate and blood pressure as well as reduced cortisol and increased oxytocin. MRI studies have also shown that gentle touching can activate key areas of the brain including the orbitofrontal and caudate cortex. Gentle touching also leads to changes in the brain's serotonin levels which may help explain why massaging can relieve pain.
Research looking into the mechanics of touch has identified specific skin receptors that relay information on physical touch to the brain. This information includes when, where, and how long the touch sensation occurs as well how gentle or rough the touching was. Depending on which skin receptors are activated (and who is doing the activating), the psychological experience of touching can be very different. Two primary skin receptors linked to the sensation of touching are:
- A-beta mechanoreceptive afferents - these are the sensory neurons located in hairy and non-hairy skin which relay neural stimuli to the brain that allows for fine discrimination of the sensation of touch. Depending on where the body is touched, what is known as crude touch can also occur in which a person is only aware that he or she has been touched but has difficulty knowing where.
- C-tactile afferents- these are found exclusively in hairy skin as opposed to hairless skin. This includes the hands, forearms, legs, and face giving these areas greater sensitivity to touch than areas of the skin that are thinly populated with afferents of either type. C-tactile afferents are most likely to be activated by pleasant stroking sensations. Even the rate at which the stroking occurs seems to make a difference in how pleasurable we might find the sensation. Stimulation of C-tactile afferents appears directly linked to the brain’s insular cortex which also regulates emotional awareness.
All of which raises some intriguing questions about how our ability to perceive pleasant touch might decrease as we grow older. Research studies looking at the touch discrimination associated with A-beta afferents have already shown that touch becomes less acute as we grow older. But what about the pleasurable aspects of touch which appear to be controlled by the C-tactile afferents in hairy skin?
Though the number of afferents found in different parts of the body actually decrease as we get older, there has been very little research on C-tactile afferents in older adults. To answer the question of how aging affects our ability to perceive gentle touch, Isac Sehlstedt of the University of Gotheburg in Sweden and a team of fellow researchers carried out an experimental study on a sample of 120 participants (60 men and 60 women) ranging in age from 13 to 82 years with a mean age of 35-36. The results, which were recently published in the journal Psychology and Aging, provide the first comprehensive look at how the sensation of pleasurable touch changes across the whole course of adult life.
After completing questionnaires measuring depression and cognitive functioning, each participant underwent a series of gentle strokes using a using a rotary tactile stimulator. With a brush made of goat’s hair to apply gentle strokes on the left forearm at different rates of speed, the experimenters were able to provide uniform tactile stimulation for all participants. After each brush stroke, participants rated the stroke in terms of pleasantness and intensity. To provide a second measure of how senses change with age, each participant also completed a standardized battery of different odours and asked to rate them in terms of pleasantness and intensity.
After the experiment, participants were asked standardized questions about how they handled being touched on a daily basis. Questions included: “I am easily bothered if someone I do not know hugs me,” “I usually seek physical contact with other people,” and “I easily get annoyed when someone (unexpectedly) touches me.”
Results showed that older adults are measurably less sensitive to being touched than younger adults are. Along with this reduced touch sensitivity, older adults also showed a greater loss of the ability to detect odours when compared to younger adults.
Interestingly enough though, these same results showed that the pleasurable sensation linked with gentle touch actually increased with age despite this reduced sensitivity to touch. This suggests that physical touch may actually become more important to us as we grow older.
One possible explanation for this finding comes from what psychologist Tiffany Field termed a “touch hunger hypothesis.” According to Field, people may be more likely to appreciate the sensation of gentle touch as they grow older because they have fewer opportunities for the kind of everyday touch we take for granted when younger. Also, older adults may be less likely to seek out opportunities for physical contact making gentle touch seem more pleasurable when it does occur.
As Isac Sehlstedt and his colleagues point out in their conclusions, these study results help demonstrate how important the sensation of gentle touch is for people of all ages. Even as we grow older, the sensation of touch plays an essential role in our psychological well-being and how we interact with other people.
So don't be reluctant to reach out and touch the people in your life. It may be more important than you think.