Psychological research has clearly demonstrated that nonverbal cues from others can cause cognitive and emotional reactions in us. These cues can alter or control our reactions and behavior, and often occur outside of our awareness. Here are 8:
1. Pupil Dilation. Research has shown that pupil dilation accompanies a sense of interest – we are interested in something and our pupils dilate to help us study it. Studies of physical attraction show that others with dilated pupils are viewed as more sexually attractive, presumably because we believe that the other person is interested in us. In ancient times, women would often dilate their pupils with belladonna to make themselves more attractive. This subtle cue definitely occurs outside our awareness.
2. Duchenne Smile. The Duchenne smile is the term given to a genuine smile – a smile that occurs because someone is happy. A Duchenne smile is distinguished from a “fake” or “polite” smile by the narrowed eyes, and “crow’s feet” at the corner of the eyes. If someone gives us a Duchenne smile, it can trigger a “genuine” smile in return. AND, when we smile, it makes us actually feel happier. This is known as the “facial feedback hypothesis.” Putting on a happy face, actually makes us happy, and, in this instance, it was all triggered by another’s smile.
3. Eyebrow Flash. The eyebrow flash is that quick raising of the eyebrows that often occurs when we recognize someone, or it can be a sign of greeting (when accompanied by a head nod). If someone eyebrow flashes us, it can cause a cognitive reaction, “Do I know this person?” and can trigger a return eyebrow flash. Similar to when someone says “good morning,” and we answer back in kind.
4. Personal Space Invasion. We carry a “bubble” of personal space around us. If someone enters our personal space bubble it causes immediate arousal. How we interpret that arousal, and how we react, depends on our assessment of the situation. Obviously, if the space invasion is from a paramour or loved one, we respond positively. However, a stranger invading our personal space can trigger irritation or fear. In those instances we typically move away and try to protect our personal space. This is one reason why we feel arousal when crowded into an elevator with strangers.
5. Gaze. Similar to personal space invasion, direct eye contact from another can also trigger arousal. How we interpret that arousal depends on who is doing the gazing, and our circumstances. There is a social rule, or norm, that allows us to make eye contact with others, but to not hold it too long, or it clearly becomes arousing. A stranger who stares at us is often viewed as a threat. We see this also in apes and other social animals (monkeys, dogs) – a direct stare can cause the animal to become agitated or threatened. Of course, if the person gazing at us is a lover (or potential lover), we can interpret eye contact as sign of interest and attraction (S/he held the gaze a bit too long. S/he’s interested.”).
6. Touch. Probably not surprising, but being touched by others can trigger a whole host of reactions. In one interesting study, waitresses in restaurants either lightly touched or did not touch the customer’s arm when giving the bill. Touching led to a higher tip. A touch or hug from someone we like orlove can trigger the release of oxytocin – known as the “love hormone” – and lead to feelings of both sexual attraction and bonding.
7. Sigh. There are many reasons why someone might let out a sigh – a feeling of sadness, longing, exhaustion, boredom, or frustration. But how does a sigh affect others? It typically leads to the question “What is wrong?” We immediately want to know why a friend or loved one let out this nonverbal cue, likely because we understand the myriad reasons why someone might sigh – but, it tends to get our attention.
8. Shrug. Although there is little research on the shrug, I suspect that shrugging creates complex reactions in others. One thing that I noted was that U.S. presidential candidate, Donald Trump, often shrugs when he is confronted on a “half-truth” or when he receives criticism about something controversial he has said. His shrug has a sort of “so what?” quality that actually stops the criticism. It seems to have the effect of psychologically “disarming” people.
As you may note, nonverbal communication is complex and depends on who is communicating and the situation. However, subtle nonverbal cues can and do have a powerful effect on others.