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According to research conducted by the National Institutes of Health, married people live longer and enjoy better health than single people do. Now, neuroscientists have shown the first experimental evidence of how affectionate contact affects the brain.
It's no secret that touch can be a pretty powerful thing—from a pat on the back to a stroke of the cheek, physical contact is one of the building blocks of social relationships. Now, neuroscientists have shown just how deep an impact touch can really have. James Coan of the University of Virginia placed 16 married women in a magnetic resonance imaging (MRI) machine, and subjected them to the threat of electric shock. He then examined the activity in his subjects' brains under three conditions—when the women were holding hands with their husbands, holding hands with a stranger or all alone. Perhaps unsurprisingly, Coan found that when the women touched their spouses, their stress levels instantly plummeted. In addition to providing the first experimental evidence of how affectionate contact affects the brain, the work may help explain why married people tend to be healthier than their single peers. The results of Coan's study will be published later this year in Psychological Science.
'Till Death Do Us Part'
According to research conducted by the National Institutes of Health (NIH), married people live longer and enjoy better health than single people do. As NIH-funded researcher Linda Waite, the director of the Center on Aging at the University of Chicago, stated in a lecture last year, "Marriage affects health. Being married, staying married, being part of a married couple changes people's choices. It changes their behaviors and that changes people's outcomes—particularly their health outcomes." According to Waite, "We've known for a long time that social [relationships] are very important for health. Things like social support, advice and help improve people's ability to deal with stress."
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In happy marriages 'Till Death Do Us Part' translates into tangible health benefits over time.
In a study published in the December 2005 issue of Archives of General Psychiatry, Janice Kiecolt-Glaser, a researcher at Ohio State University, demonstrated a specific and tangible health benefit of a happy marriage. Kiecolt-Glaser and her team studied more than 40 couples to determine the effects of marital behaviors on blister wound healing. The researchers found that individuals healed faster following a supportive interaction with their spouses than they did after a disagreement. In fact, according to Kiecolt-Glaser, "Couples who demonstrated consistently higher levels of hostile behaviors . . . healed at 60% of the rate of low-hostile couples."
Shocking, Really
Coan and his colleagues decided to see what effect a happy marriage has on the brain when an individual is under stress. They began by recruiting couples from the greater Madison, Wisconsin area via newspaper advertisements. In order to ensure that their participants were happily married, the researchers assessed them using the Dyadic Adjustment Scale (DAS), a test widely used to measure relationship quality. After excluding pairs whose DAS scores were too low, Coan narrowed the group down to 16 "highly satisfied" couples. He invited each couple to the lab for two visits; the first to familiarize the participants with the experiment and the MRI scanner, and the second to actually conduct the experiment.
In order to stress out the wives in his study, Coan attached shock electrodes to their ankles before leading them to the MRI chamber (the lucky husbands had the role of hand-holder.) Once in the MRI scanner, the wives were shown a series of cues—12 safety cues consisting of a blue "O" against a black background, and 12 threat cues consisting of a red "X" on a black background. The threat cues indicated that there was a 20% chance the women would receive a shock, while the safety cues indicated that there was no chance a shock was coming. After each cue, there was a 4-10 second anticipation period, followed by either a shock or a signal to tell the women the cue trial was over.
Each woman was exposed to three blocks of 24 cues (12 safety cues and 12 threat cues). In one block, the wives held their husbands' hands. During another, they held the hand of an anonymous male experimenter. In the remaining block, the women were all alone—no hand-holding was provided. The order in which the women were exposed to the different blocks varied from subject to subject. Following each block, the wives provided a subjective rating of their experience during the trial.
Just a Little of That Human Touch
Coan and his team found that holding hands with their spouses reduced the self-reported unpleasantness and agitation that the wives experienced. Even more significantly, Coan found that the physical contact with their husbands had a considerable effect on the wives' functional MRI readings. Coan determined that when the wives held hands with their husbands, neural activation was appreciably less in the ventral anterior cingulated cortex (ACC), left caudate, superior colliculus/midbrain, posterior cingulated cortex, left supramarginal gyrus and right post central gyrus—all regions of the brain involved in emotional and behavioral threat responses. Though holding hands with the stranger also calmed the women down to some degree, Coan found that contact with a spouse was far more effective.
Coan also determined that the woman's response to her husband's touch depended on the quality of the marriage. He found that women in "supercouples"—couples with the highest DAS scores—also had less neural activation in the superior frontal gyrus, hypothalamus and right anterior insula than women in less tightly-knit couples did. One of these regions, the right anterior insula, is involved in anticipating and processing pain—indicating that the touch of a "superhusband" could not only calm his partner, but act as a form of anesthesia as well.
Other researchers have praised Coan and his team for their innovative approach; as Ronald Glaser, the director of the Institute for Behavioral Medicine Research at Ohio State University, told the New York Times, "This is very imaginative, cutting-edge science, linking this complex response to stress to different areas of the brain." Not only does Coan's study illustrate the importance of that human touch, it may help solve the mystery of why married people live longer. As Coan told the Times, "The effect of this simple gesture of social support is that the brain and body don't have to work as hard, they're less stressed in response to a threat." So snuggle up with someone special, or get out there and find yourself a Valentine—after all, it's good for your health.
Bibliography
Carey, Benedict. "Holding Loved One's Hand Can Calm Jittery Neurons." New York Times, January 31, 2006, page F7.
Coan, James et al. "Lending a Hand: Social Regulation of the Neural Response to Threat." Psychological Science, (awaiting publication).
Garnett, Carla. "Want a Long, Healthy Life? Get, Stay Married, Says Waite." NIH Record (January 4, 2005) [accessed February 1, 2006]: www.nih.gov/ nihrecord/ 01_ 04_ 2005/ story01.htm.
Kiecolt-Glaser, Janice et al. "Hostile Marriage Interactions, Proinflammatory Cytokine Production and Wound Healing." Archives of General Psychiatry, December 2005, page 1377.