The NonVerbal Dictionary of Gestures, Signs & Body Language Cues

Zygomatic Smile

She gave me one of those smiles the lips have forgotten before they reach the eyes. --Philip Marlowe, describing client's daughter, Vivian Regan (The Big Sleep, 1939:60)

Facial expression1. A true smile of happiness, gladness, or joy. 2. An expression in which the corners of the mouth curve upward, and the outer corners of the eyes crinkle into crow's-feet.

Usage: Though we may show a polite grin or camera smile at will, the zygomatic or heartfelt smile is hard to produce on demand. While the former cue may be consciously manipulated (and is subject to deception), the latter is controlled by emotion. Thus, the zygomatic smile is a more accurate reflection of mood.

Anatomy. Lip corners curl upward through contraction of zygomaticus muscles; crow's-feet show when the zygomaticus muscles are strongly contracted, and/or when orbicularis oculi muscles contract. In the polite (i.e., intentional, weak, or "false") smile, lip corners stretch sideward through contraction of risorius muscles, with little upward curl and no visible crow's-feet.

Evolution. The smile-face may be traced to the primate's grimace or fear grin. The submissive grin, used to show "I am afraid," came to suggest that "I am harmless--and therefore friendly--as well" (Morris 1994). The link between smiling and humor, love, and joy has yet to be explained.

Feedback smile. Smiling itself produces a weak feeling of happiness. The facial feedback hypothesis proposes that ". . . involuntary facial movements provide sufficient peripheral information to drive emotional experience" (Bernstein et al. 2000). According to Davis and Palladino (2000), ". . . feedback from facial expression [e.g., smiling or frowning] affects emotional expression and behavior." In one study, e.g., participants were instructed to hold a pencil in their mouths, either between their lips or between their teeth. The latter, who were able to smile, rated cartoons funnier than did the former, who could not smile (Davis and Palladino 2000).

Media. 1. "So, there's the 1984 study that found that ABC News anchor Peter Jennings was more likely to smile on camera when talking about Ronald Reagan than Walter Mondale, and that in the same year the people who watched ABC News voted for Reagan in greater proportions than the people who watched other network-news shows" (Lacayo 2000:90). 2. "Who has the most coveted smile in Hollywood? 'Twenty years ago, everyone wanted a smile like Farrah Fawcett's,' says Dr. Irving Smigel, a New York dentist who created the Supersmile product line . . . and has worked on Calvin Klein and Johnny Depp. 'Now most of my patients mention Julia Roberts. Her mouth is very feminine'" (Comita 2000:80).

Supermarket mandatory smile. In the late 1990s, Safeway, the second largest supermarket chain in the U.S., instructed its store employees to smile and greet customers with direct eye contact. In 1998, USA Today ("Safeway's Mandatory Smiles Pose Danger, Workers Say") reported that 12 female employees had filed grievances over the chain's smile-and-eye-contact policy, after numerous male customers reportedly had propositioned them for dates. Commenting on the grievances, a Safeway official stated, "We don't see it [the males' sexual overtures] as a direct result of our initiative."

Salesmanship. "You don't have to smile constantly to show you are enjoying yourself. Smile at the peaks" (Delmar 1984:41).

Smiley face. The yellow "smiley face," a popular graphic symbol designed by commercial artist Harvey Ball in the early 1960s, has become a universal sign of happiness. Its color is associated with the brightness of the sun (see COLOR CUE). According to his son, Charlie Ball, Harvey ". . . understood the power of it (the smiley face) and was enormously proud of it [even though others, rather than Ball, profited financially from the design]. He left this world with no apologies and no regrets, happy to have this as his legacy" (Woo 2001:A6). Designed to enhance the Worcester, Mass.-based State Mutual Life Assurance company's "friendship campaign," to bolster employee morale, the smiley face took Ball about 10 minutes to complete (Woo 2001). "Fearing that a grumpy employee would turn the smile upside down into a frown, he [Ball] added the eyes" (Woo 2001:A6; see ISOTYPE).

RESEARCH REPORTS1. Regarding the fake smile, "Dr [Guillaume-Benjamin] Duchenne [de Boulogne] attributes the falseness of the expression altogether to the orbicular muscles of the lower eyelids not being sufficiently contracted" (Darwin 1872:202). 2. The smiling play-face is seen "when a child is about to be chased by another and stands slightly crouched, side-on to the chaser and looking at it with this 'mischievous' expression, an open-mouthed smile with the teeth covered, which morphologically resembles the 'play-face' of Macaca and Pan" (Blurton Jones 1967:358). 3. "But one sometimes feels that human smiles are also partly 'fear' motivated" (Blurton Jones 1967:364). 4. "The comparative data show that there is a similarity in form between the smiling response and the silent bared-teeth face" (Van Hooff 1967:60). 5. Brannigan and Humphries (1969) identified the "simple smile," the "broad smile," and the "upper smile" (the latter two are zygomatic smiles).6. "Exogenous" smiling, not present at birth, begins at about three weeks as an unpredictable, fleeting response to audio, visual, or tactile stimuli; "social" smiling (e.g., to faces) becomes predictable by 8-to-12 weeks (Spitz, Emde and Metcalf 1973). 7. By the age of four, boys ". . . are reserving the 'sociable' upper smile [in which the lips are parted to reveal the top teeth] for other boys almost exclusively. The girls, while not using the upper smile as exclusively as do the boys, appear, by age 4, to use this smile rarely with boys" (Cheyne 1976:823). 8. "The data indicated that the infants looked at the joy expression significantly more than at either the anger or neutral expressions" (LaBarbera et al. 1976:535). 9. "My research suggests that with enjoyment the zygomaticus major muscle is the principal muscle in the lower face, and may be the only active muscle in the lower face" (Ekman 1998:201). 10. ". . . five-month-old infants show the eye-muscle smile when the mother approaches, but a smile without the eye muscle when approached by a stranger" (Ekman 1998:203).

E-Commentary: "I am a journalist who was referred to you by the American Anthropological Association, for a story I am working on for the Boston Globe Sunday magazine about the anthropological origins of the smile, its evolution over time, and ways that we use it today. In addition to that general theme, I am exploring the degree to which regional differences and cultural influences may affect the frequency with which we smile. For example, Bostonians are stereotypically known as non-smilers, while Southern Californians are often pictured to be as sunny as their weather." --M.F. (6/13/00 11:58:09 AM Pacific Daylight Time)

Neuro-notes I. The zygomatic smile is controlled ". . . from the anterior cingulate region, from other limbic cortices (in the medial temporal lobe), and from the basal ganglia" (Damasio 1994:140-41). "We cannot mimic easily what the anterior cingulate can achieve effortlessly" (Damasio 1994:141-42).

Neuro-notes II. Mirror neurons play a role in decoding the smile: "Baby smiles, the parent smiles in response. Two minutes later, baby smiles again, the parent smiles again. Thanks to the imitative behavior of the parent, the baby's brain can associate the motor plan necessary to smile and the sight of the smiling face. Therefore--presto! Mirror neurons for a smiling face are born" (Iacoboni 2008:133-34).


Read the Boston Globe Magazine feature, "Grin and Bare it."

View 60 seconds of a man's "on-purpose" smile. (Mute the sound to avoid a distracting commercial message.)

Photo of "Smile, Surfacing" (Fiesta Mexicana, Spokane, Washington, USA) by Doreen K. Givens (copyright 2007)