It had been seven weeks since I’d touched another human being. Arms outstretched, I walked quickly toward my dad, craving his embrace. In the instant before we touched, we paused, our minds probably running quick, last-minute calculations on the risk of physical contact. But, after turning our faces away from each other and awkwardly shuffling closer, we finally connected. Wrapped in my dad’s bear hug, I momentarily forgot we were in the midst of the worst global crisis I have ever experienced.

“Touch is the most powerful safety signal of togetherness,” says Steve Cole, a psychiatrist and biobehavioral scientist at the University of California, Los Angeles.

Like more than 35 million other Americans, I live alone, and with the guidelines of physical distancing set by the Centers for Disease Control and Prevention, I hadn’t been getting close to anyone to avoid being...

“When we get lonely and isolated our brainstem recognizes that suddenly we are in insecure territory and flips on a bunch of fight-or-flight stress responses without us even knowing it,” Cole says. “There’s all sorts of things in our social world that lead us to calculate that we are either safe or unsafe. You can think of physical touch, supportive and affectionate touch, as the most fundamental signal that you’re with somebody who cares about you . . . a fundamental signal of safety and well-being.”

What touch does to the immune system

Stress, which for many of us during the coronavirus pandemic has grown considerably, can flood the body with hormones, such as cortisol and adrenaline, as part of the fight-or-flight response. Left to build up over time, those accumulating stress hormones can lead to high blood pressure, heart disease, and growing levels of anxiety.

Touch is hitting all of the right buttons to affect physiological processes that are that are critically important to keeping us healthy.

—John Capitanio, University of California, Davis

The feeling of security that comes with holding hands or hugging is a result of a cascade of physical and biochemical changes in the body and the brain that can counter the fight-or-flight response. Tiffany Field, the director of the Touch Research Institute at the University of Miami Miller School of Medicine, has been studying that cascade of changes for more than three decades, focusing mainly on the effects of massage. What she and others have shown is that anything that moves the skin with a bit of pressure—hugging, holding hands, massage—stimulates pressure receptors beneath the skin. Those receptors then send electrical signals to the vagus nerve, a superhighway of the nervous system with thoroughfares leading to nearly every organ of the body and a direct line into the brainstem, which automatically regulates breathing, blood pressure, and heart rate.

When the vagus nerve gets touch signals and directs them to the brainstem, it, in turn, sends another set of signals to slow the heart and nervous system, Field says. The body then tamps down the amount of stress hormones it produces. 

With levels of cortisol, the body’s main stress hormone, on the decline, “you’re saving natural killer cells,” Field says. Cortisol, studies suggest, may repress the ability of natural killer cells to secrete proteins that aid in immune cell migration and in the initiation of cell death pathways in infected cells or cancerous cells. In Field’s studies in men with HIV and women with breast cancer, she found that massage resulted in a 30 percent reduction in cortisol, which in turn led to increased activity of natural killer cells.

Bolstering that connection between touch and the immune system is a study, published online in 2014, that found that hugging might lower a person’s susceptibility to infection by viruses that cause the symptoms of a common cold. In the experiment, Carnegie Mellon University psychologist Sheldon Cohen and colleagues asked more than 400 adults to complete a questionnaire to assess their perceived emotional support, specifically if participants felt they had trusted companions to listen to their problems or to spend time with doing activities they both enjoyed. The team then called the study participants each night for 14 nights to record their levels of daily interpersonal conflict and the number of hugs they received. Next, the volunteers had either rhinovirus or influenza A sprayed into their noses, and the team assessed how they responded to infection. Having higher stress and lower levels of social support was tied to the participants’ risk of getting sick. Having more frequent hugs was also associated with a decreased risk of infection, the researchers showed.

Touch is “hitting all of the right buttons to affect physiological processes that are critically important to keeping us healthy,” says John Capitanio, a psychologist and primatologist at the University of California, Davis. The benefits are so great that in the past few years people have begun paying for platonic cuddle time, according to The Washington Post.

What touch does to the brain

As cortisol eases up and heart rate slows down, nerve cells release the neurotransmitter serotonin in response to affectionate touch. “Serotonin is the body’s natural antidepressant and antipain chemical,” Field says. 

Affectionate touch with a bit of pressure also leads to better sleep, and better sleep lowers the body’s emission of the neurotransmitter substance P, which transmits pain. Touch, Field says, can also increase dopamine, a neurotransmitter associated with reward, and oxytocin, often called the cuddle hormone. A number of studies show that when a couple hugs each other before a stressful task, cortisol decreases and oxytocin increases, she explains. Touch from a trusted person, for example, buffers the usual effects of stress leading to the feeling of more pain.

Our brainwaves are also influenced by touch. One of Field’s studies showed that medical school students who received short chair massages experienced changes to their brainwaves in the direction of relaxation. Theta waves, which are representative of relaxation, increased, as did the students’ cognitive performance. They were able to do a mathematical computation in half the time and with higher accuracy, on average, after receiving the chair massage.

This kind of research clearly shows the importance of touch, Capitanio says. “It affects our nervous system. It affects our immune system. It affects hormonal systems. It affects a lot of different stuff.”

Pressure matters

How the skin is touched is important. Field’s research has shown that light touches or strokes on the skin are arousing, increasing the heart rate and generating more beta, instead of theta, waves in the brain. It’s similar with babies born prematurely; if you lightly stroke them, they’ll arch their backs, whimper, and scrunch up their faces. Apply a little pressure, however, and the babies remain relaxed, receptive to the touch. In the long-term, they gain weight more easily and have better overall health than those not getting a massage. “It seems counterintuitive for premature babies because they seem so fragile,” she says, “but it has benefits.” 

The same logic applies to individuals craving touch in the face of the anxiety associated with the COVID-19 pandemic, Field suggests. Her studies have repeatedly shown that affectionate touch with a bit of pressure can ease anxiety. And, Field notes, that type of touch doesn’t even have to come from another individual. You can do it to yourself with a self-massage or any moderately pressured movement of the skin, such as yoga. Even the pressure provided by exercise can help, she says.  

It’s easy to enact. . . . It’s hard to mess up.

—Brooke Feeney, Carnegie Mellon University

She and her colleagues just finished conducting a survey—the results of which haven’t been published yet—to assess how people are faring during the pandemic. Of the 260 people that responded, sleep problems, fatigue, and anxiety ranked highest among the concerns. A little less than half reported feeling lonely or touched deprived, and 58 percent reported feeling isolated, with roughly 28 percent of all participants living alone. After a preliminary analysis of the data, the team has found that “exercise is related to all the positive measures that we took,” Field says, and none of the negative ones. Yoga, for example, stimulates those pressure receptors under the skin that send signals to the vagus nerve and kicks off the cascade of touch-based benefits. “Exercise is turning out to be the most positive thing to do,” she says.

The touch of another

But exercise or self-massage may not be enough to alleviate anxiety, some scientists suggest. Capitanio, a primatologist, says, “sociability is embedded in our genes.” Humans share a common ancestor with rhesus macaques dating to millions of years ago, and that ancestor, according to the fossil record, was a social creature living in groups, just as macaques do today and as humans tend to do too. “Sociality has been a really important part of our biology for millions of years,” Capitanio says, and touch is a part of that sociability. 

Brooke Feeney, a psychologist at Carnegie Mellon University, agrees. She was not part of the team that ran the study on hugging and risk of viral infection, but she has spent a considerable amount of time researching touch and has found it to be a “simple yet effective intervention for improving relationships and enhancing social connection,” she writes in an email to The Scientist. Her work suggests that not only is the physical sensation of touch important, but so is the meaning behind it.

“When someone is touched affectionately, they interpret the meaning of that touch. Affectionate touch typically communicates that someone is available to be supportive as needed, and it communicates that one is valued and accepted. It is a salient reminder that one is valued, included, accepted, loved and cared for,” she says. “It indicates that one is included in a social group. And a reminder of one relational connection, through a simple touch, can increase the salience of one’s social inclusion broadly, promoting feelings of security and having health-protective effects.”

Affectionate touch is the optimal form of offering support, says Feeney, who is also currently conducting a survey on the social effects of COVID-19. “It’s easy to enact. . . . It’s hard to mess up.”

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