Study: Humans Can 'Talk' Through Touch
MADELEINE BRAND, host:
Scientists are discovering that when you touch someone, you communicate very specific emotions such as sympathy, disgust, gratitude, or even love. The current issue of the scientific journal Emotion features a series of studies about touch. Reporter Michelle Trudeau touched base with the lead researcher.
MICHELLE TRUDEAU: Psychologist Matt Hertenstein from DePaul University in Green Castle, Indiana decided to study touch while he was watching parents interacting with their babies - making faces and cooing sounds, squeezing, stroking, nuzzling them.
Mr. MATT HERTENSTEIN (DePaul University): And all of a sudden it struck me one day and I thought, you know, I wonder if touch can communicate distinct emotions, much like the face and the voice.
TRUDEAU: Decades of research has been done on the face and the voice and the distinct emotions that they communicate. But touch has been relatively neglected by researchers until Hertenstein stepped in and began his experiments.
Mr. HERTENSTEIN: We invited two participants into the lab.
TRUDEAU: Two at a time, strangers to each other.
Mr. HERTENSTEIN: And we put a curtain up between those two people so they couldn't see or hear each other.
TRUDEAU: One participant, the sender, was told to try and communicate twelve different emotions, one by one, to the other participant, the receiver.
Mr. HERTENSTEIN: The receiver would put his or her arm underneath the curtain, on to the sender's side.
TRUDEAU: The sender would then touch the receiver's forearm, trying to communicate the specific emotion, such as envy, fear, love, embarrassment, anger, gratitude, pride, disgust. The receiver had to then decide which emotion was being communicated. Hertenstein tested over 200 participants.
Mr. HERTENSTEIN: Lo and behold, and honestly to our surprise, six out of the 12 emotions that we studied were accurately communicated to the receiver.
TRUDEAU: Before this study, there was only evidence that touch could communicate the general gist of whether an emotion was positive or negative, what researchers call the valance of the emotion, like warmth and intimacy versus pain and discomfort. But this study shows for the first time that touch can successfully, reliably communicate several distinct emotions.
Mr. HERTENSTEIN: And specifically, anger, fear, disgust, love, gratitude and sympathy were accurately communicated at far above chance levels.
TRUDEAU: In fact, the accuracy rate of touch is equal to that of emotions communicated by the face or the tone of voice. There were some emotions, though, that touch didn't convey well.
Mr. HERTENSTEIN: The emotions that were not communicated accurately were some of the self-focused emotions, which were embarrassment, envy, pride; and then surprise, happiness and sadness were not accurately decoded at above chance levels.
TRUDEAU: Hertenstein videotaped the participants and analyzed frame by frame the touch movements. He found that there were certain consistent characteristics in the way the sender touched the receiver's arm. For example, for anger it was hitting or squeezing.
Mr. HERTENSTEIN: Fear was characterized by a lot of trembling, happiness by swinging, disgust by pushing and lifting. Sympathy was communicated by patting and stroking and rubbing. And love was communicated by stroking and finger interlocking. So we did find distinct touch behaviors that characterize each of the emotions.
Dr. TIFFANY FIELD (University of Miami School of Medicine): I think it's very exciting. I think it will be a seminal article.
TRUDEAU: Seminal says researcher Tiffany Field, because touch is so vital to human interactions and yet so little is known about it. Field is director of the Touch Research Institute at the University of Miami School of Medicine. Touch, she says, is critical for growth and development. It is, in fact, the first sense to develop in a fetus before seeing or hearing, and the most highly developed sense at birth. Now Hertenstein's studies have uncovered an additional essential role of touch: to reliably communicate specific emotions. For NPR News, I'm Michelle Trudeau.