Dacher Keltner, PhD

Our appearances and actions often say more about our feelings than our words. Even the smallest gesture — such as a head-tilt or a smile — can reveal a lot, according to social psychologist Dacher Keltner, PhD.

“The body is a powerful tool for communication,” says Keltner, a professor and founding faculty director of the Greater Good Science Centeropens in new window at the University of California, Berkeley. “When we measure gestures scientifically by coding facial expression, vocalization or patterns of touch, we get this remarkably faithful assessment of who a person is and what they’re feeling.”

Keltner and his colleagues measure nonverbal communication by analyzing people’s facial expressions to assess what they are feeling.

“We wondered if people reveal emotions such as sexual desire or long-term love in little changes in facial appearances,” adds Keltner. “We had romantic partners come into the lab and recorded them talking about how they fell in love, and then we gathered data from them about how much they loved each other, whether they felt sexually attracted to each other, whether they were committed.” 

Keltner then compared his data with nonverbal communication cues in the nonhuman primate world where partners lick and pucker their lips before copulation. 

“Lo and behold, little half-second bursts of lip puckers and lip licks in our human subjects correlated with feeling sexually attracted and being happy sexually,” he continues. “In contrast, in the primate world, tender warmth is signaled by head tilts and open-handed gestures and warm smiles, and sure enough, in our human couples, we found that little one-second bursts of those behaviors correlated with feeling love, wanting to get married and talking about a long-term life together.”

Beyond facial expression analysis, Keltner’s research also shows that emotion can be communicated through touch. 

To find out how much, Keltner and colleagues brought people into a lab and removed their ability to see or hear each other. They then had the subjects try to communicate different emotions just by a touch to the forearm.

According to Keltner, the team learned a lot about emotion by analyzing small touches between the research subjects. The individuals in the study were able to send and receive emotions like anger, fear and disgust via one-second touches. Feelings of sympathy, gratitude and love were also made clear through touch. 

“We’re now learning that physicians are taking the science of compassion and gratitude and touch and learning how to be more empathetic doctors,” Keltner says. “This is important because new findings show that the more patients feel a compassionate connection to their doctors, the longer they live in the face of disease.” 

Other work is showing that touch calms stress-related physiology in rat pups, and that it’s good for their immune systems. 

“I see enormous hope in where this science will go in shaping our society,” says Keltner.