A smile can be sincere, or pure politeness. The difference often shows around the eyes: when a smile is real, little creases appear at the corners of the eyes and the cheeks lift.
Here’s what science and synergology say about it, and why it pays to be careful before deciding a smile is fake.
Key takeaways
- The “Duchenne smile” uses two muscles: the one that lifts the corners of the mouth and the one that creases the area around the eye.
- In 1990, Ekman, Davidson and Friesen showed that this smile goes with genuinely felt enjoyment more often.
- It can still be faked: in 2009, a study found just as many Duchenne smiles in people smiling on request.
- No crow’s feet is a clue, not proof: also look at timing, length and context.
What is a real smile?
It’s a smile that involves the eyes as much as the mouth. In the 19th century, French neurologist Guillaume Duchenne de Boulogne used electrical stimulation on facial muscles to map expressions. In Mécanisme de la physionomie humaine (1862), he distinguished two muscles:
- the zygomaticus major, which pulls the corners of the mouth up, and which is easy to control;
- the orbicularis oculi, which circles the eye, lifts the cheeks and creates the famous crow’s feet.
According to Duchenne, this second muscle doesn’t obey the will well and only really activates with a pleasant emotion. That’s why a smile that uses both is now called a “Duchenne smile”.
What does research say about the Duchenne smile?
It confirms the link with enjoyment. In 1990, Paul Ekman, Richard Davidson and Wallace Friesen filmed participants’ faces while they watched pleasant or unpleasant films, and measured their brain activity at the same time (Ekman, Davidson and Friesen, Journal of Personality and Social Psychology, 1990).
Smiles that involved the muscle around the eye showed up more often during the pleasant films. They also matched the enjoyment participants reported feeling, which wasn’t the case for other smiles.
Can you fake a smile with your eyes?
Yes, more often than you’d think. In 2009, Eva Krumhuber and Antony Manstead asked participants either to smile spontaneously at amusing material or to smile on request. They found similar proportions of Duchenne smiles in both situations (Krumhuber and Manstead, Emotion, 2009).
Good news for observers, though: people who watched these smiles could generally tell spontaneous smiles from posed ones. So crow’s feet aren’t enough on their own. The rest of the face, and especially the moment the smile appears, matter too.
How can you recognise a sincere smile in everyday life?
By combining several clues. Here are the ones that come up most often in training:
- The eyes: crow’s feet, lifted cheeks, slightly raised lower eyelids.
- The timing: a real smile follows whatever triggers it; a polite smile often comes too early or too late.
- The rhythm: a sincere smile builds and fades gently; a forced one switches on and off all at once.
- The rest of the body: do the hands, posture and voice point the same way?
- The context: an official photo, a tense meeting and dinner with friends don’t call for the same smile.
What synergology adds to reading a smile
Synergology doesn’t stop at the smile: it reads it together with the rest of the face and body. It pays special attention to asymmetry, since each half of the face can tell a different story. We explain this in detail in our article on the Mona Lisa’s smile.
The approach stays the same: spot a gap, form a hypothesis, then check it through conversation. A smile without crow’s feet doesn’t make someone a liar; it’s simply a reason to pay closer attention.
Frequently asked questions about real and fake smiles
What is a Duchenne smile?
It’s a smile that activates both the zygomaticus major, which lifts the corners of the mouth, and the orbicularis oculi, which creases the area around the eyes. It’s named after neurologist Guillaume Duchenne de Boulogne, who described it in 1862. It’s associated with genuinely felt enjoyment.
Is a smile with no creases around the eyes always fake?
No. A polite smile, a slight smile or a photo taken at the wrong moment may not crease the eyes. No crow’s feet is one clue to combine with others, such as the moment the smile appears and the rest of the body language.
Can you fake a smile with your eyes?
Yes. A 2009 study (Krumhuber and Manstead, Emotion) found as many Duchenne smiles in people smiling on request as in people smiling spontaneously. Observers could still often tell the difference by looking at the whole face.
How can I learn to read emotions on a face?
By observing a lot, ideally on video rather than in photos, and checking your hypotheses through conversation. Synergology training gives you a structured reading grid and hands-on exercises. Our free quiz is also a good way to gauge your level.
Go further: put your eye to the test with our free non-verbal communication quiz, or explore our synergology training.
