With her mouth is wide open, teeth bared and eyes pressed tensely shut, tennis star Serena Williams looks a picture of pure anger in this close-up photograph.
Has she just lost the final of a Grand Slam? Or perhaps had to withdraw through injury?
Or is she, in fact, ecstatically happy?
When the image is widened out to include her body language the answer is made more clear.
The pumped fist is an indicator of her happiness and, as it happens, this photograph was actually taken at the moment she defeated her sister Venus at the 2008 U.S. Open.
The difficulty of identifying her emotion in the close-up photo occurs because context is vital to interpreting facial emotion, according to a new psychology paper.
‘Humans are exquisitely sensitive to context, and that can very dramatically shape what is seen in a face,’ says psychologist Lisa Feldman Barrett Massachusetts General Hospital and Harvard School of Medicine.
‘Strip away the context, and it is difficult to accurately perceive emotion in a face.’
Barrett’s paper, written in conjunction with graduate student Maria Gendron and Batja Mesquita of the University of Leuven in Belgium, has been published in the journal Current Directions in Psychological Science.
The paper refutes the contention that there are six to 10 biologically basic emotions, each encoded in a particular facial arrangement, which can be read easily in an image of a disembodied face by anyone, anywhere.
The perception of facial-emotionals is influenced by many kinds of contexts, says the study.
A scowl can be read as fear if a dangerous situation is described, or as disgust if the posture of its body indicates reaction to a soiled object.
Eye-tracking experiments show that, depending on the meaning derived from the context, people focus on different salient facial features.
Suggestion and certain words affected facial perception in the study, with participants routinely doing better at naming the emotions in pouting, sneering, or smiling faces when the experimenter supplied words to choose from than when they had to come up with the words themselves.
Equally important is the cultural context of an expressive face.
People from cultures that are psychologically similar can read each other’s emotions with relative ease, an effect that similar language or even facial structure does not produce.
Culture even influences where a person seeks information to interpret a face. Westerners, who see feelings as inside the individual, focus their attention on the face itself. Japanese, meanwhile, focus relatively more on the surroundings, believing emotions arise in relationship.
The implications of such research are ‘substantial,’ says Barrett, who believes it could help understand changes in emotion in people with with dementia or certain psychopathologies, and even in healthy older people, who may have difficulty expressing themselves.
There are also implications for law enforcement where some U.S. agencies are training people to detect deception using methods based on the idea that a person’s internal intentions are broadcast on the face.