LIP SERVICE

A winning smile is widely recognized as social currency even by our primate cousins, but—as LaFrance (Psychology/Yale Univ.) shows—its meaning is not always so obvious.

The author deconstructs the hidden content of smiles and their role in our lives, beginning with the startling information that babies have been observed to practice smiling while still in the womb. This is believed to be an unconscious survival mechanism that prepares them to elicit the care they need from adults in order to survive, rather than a spontaneous expression of pleasure. The author identifies this act as the baby's social manipulation. By five or six weeks, the infant has learned to lock eyes with caretakers and smile responsively. “[E]volution has made that behavior adaptive,” she writes, providing “babies with the ability and inclination to flex their smile muscles but maturity and social context affect whether, when and how they will materialize.” Smiles are recognizably spontaneous or voluntary, engaging different neural pathways and involving different facial muscles; and they can represent a panoply mixed emotions, which are recognizable according to the facial muscles they engage, their size and duration. Humans are wired to respond empathetically to the smiles of others, and experimental evidence suggests that people who smile more tend to live longer because the act evokes a positive emotional state. Psychologists describe this as the “facial feedback hypothesis.” LaFrance presents an abundance of contemporary research to demonstrate how our smiles are conditioned socially. Women tend to smile more than men, people in power positions smile less than their subordinates and service-with-a-smile is expected. Americans smile at the children of strangers, while Europeans don't, and there are subtle differences between the smile of an Englishman and an American, or a French woman and a French-speaking Canadian—as discernible as their different accents. By unveiling the complexity of something as simple as a smile, the author provides surprising insights into culture and psychology.