Less is more: Study looks into the traits of a “perfect” smile
MINNEAPOLIS, Minn., USA: Lopsided, big, toothy, shy—smiles are described in many different ways. However, how people perceive the facial expression in social interaction and nonverbal communication can differ significantly, new research from the University of Minnesota has found.
In the study, the researchers asked 802 study participants to rate 27 computer-animated smiles on their perceived effectiveness (very bad to very good), genuineness (fake vs. genuine), pleasantness (creepy to pleasant) and emotion expressed (anger, contempt, disgust, fear, happiness, sadness or surprise). The animated expression was altered by variations in the mouth angle, the extent of the smile, the degree to which teeth were shown and how symmetrically the smile developed.
The findings suggest that for a winning smile—one that is perceived as effective, genuine and pleasant—less is more. In the study, smiles with a medium angle tended to be more favorably judged, while wide open-mouth smiles were often interpreted as a sign of fear or contempt. In fact, the two lowest-rated smiles were both very toothy.
Although research has suggested that facial symmetry is often perceived as being more beautiful than asymmetry, slightly crooked smiles were rated higher in the current study. According to the researchers, this result is consistent with principles of smile design, in which dynamic symmetry, that is being very similar but not identical, allows for a more vital, dynamic, unique and natural smile compared with static symmetry.
The study’s results could have broad applications in a variety of areas, such as facial reanimation surgery and rehabilitation in individuals who have suffered from trauma, cerebrovascular accidents, neurological conditions, cancers or infections that have robbed them of the ability to express emotions through facial movement, the researchers concluded.
The psychological and social consequences of facial impairment can be extensive. Research has shown that individuals with partial facial paralysis are often misinterpreted, have trouble communicating, become isolated, and often report symptoms such as anxiety and depression.
The study, titled “Dynamic properties of successful smiles,” was published on June 28 in the PLOS ONE journal.