Why Mirroring Doesn’t Always Work

Mirroring (also known as isopraxism), or copying another person’s posture and movements, has become one of the most popular techniques for establishing or improving communication due to its simplicity. However, as is often the case, a simple technique is frequently used ineffectively—and sometimes even with the opposite of the intended result. Why does this happen?

One possible reason is a literal interpretation of the term: since it’s called “mirroring,” people try to become a “mirror” and copy the other person’s movements exactly. This approach overlooks the fact that literal mirroring can, first, provoke irritation (the person you’re talking to may also have heard about NLP and doesn’t like being manipulated), and second, it looks extremely unnatural. Unnatural behavior, for example, can be a signal that someone might be lying.

This raises several questions: Is isopraxism effective? If so, to what extent should you copy someone’s posture for it to seem natural? And can isopraxism be used to detect deception? I’ll try to answer these questions here.

How Effective Is Mirroring?

Copying someone’s posture during communication is effective. Figuratively speaking, the brain perceives your conversation partner’s movements as your own, which requires less time and energy. As a result, spending less energy analyzing the other person’s behavior leads to perceiving them more positively.

Interestingly, people who are engaged with each other (not necessarily flirting—this can also happen between business partners during negotiations) unconsciously imitate each other’s posture. For a long time, the answer to how much you should copy someone else’s posture was: “Within reasonable limits, trying not to cross the line of being noticeable.”

This created practical problems—what does “within reasonable limits” mean, and how do you determine them? An interesting study (Sparenberg P., Topolinski S., Springer A., and Prinz W. (2012). Minimal mimicry: Mere effector matching induces preference. Brain and Cognition, 80 (3), 291-300) provides answers to these questions.

The study evaluated the effect of different degrees of movement copying on how positively the opponent was perceived. In the first series of two experiments, the opponent was an avatar on a screen; in the second series, it was a real person. Both avatars and people copied movements to varying degrees—from full imitation to completely mismatched movements. At the end of the experiment, participants rated their feelings toward the avatar or person. The most positive ratings were given to those who moved the same limb, regardless of the type of movement.

The research showed that simply moving the corresponding arm or leg is enough to create a positive communicative effect. Importantly, the corresponding arm or leg just needs to move—it doesn’t have to copy the exact movement or intensity of your conversation partner.

Rule: If your conversation partner moves their right hand, you move your right hand, without copying their specific movements or intensity. The same applies to other limbs.

Mirroring and Detecting Deception

To answer the third question about using isopraxism to detect lies, I’d like to reference an interesting study by researchers at Utrecht University (Mariëlle Stel, Eric van Dijk, Einav Olivier. “You Want to Know the Truth? Then Don’t Mimic!” Psychological Science, June 2009, vol. 20, no. 6, pp. 693-699). They started from the idea that isopraxism improves empathy, or the ability to understand another person’s feelings. In the experiment, participants judged whether statements were true or false while either copying or not copying the storyteller’s body language and facial expressions. It turned out that those who did not mimic were much more accurate in determining the truthfulness of the statements.

Therefore, when using isopraxism to detect lies, it’s important to understand when you’re copying someone’s movements to “connect” with them, and when you should reduce the intensity of mirroring to improve your ability to detect deception.

Looking at isopraxism from the liar’s perspective, we see that the intensity of mirroring drops sharply under cognitive load, at the moment of orientational freezing, giving us an additional signal that deception may be present.

Sources and Further Reading

• Sparenberg P., Topolinski S., Springer A., and Prinz W. (2012). Minimal mimicry: Mere effector matching induces preference. Brain and Cognition, 80 (3), 291-300.
• Mariëlle Stel, Eric van Dijk, Einav Olivier. “You Want to Know the Truth? Then Don’t Mimic!” Psychological Science, June 2009, vol. 20, no. 6, pp. 693-699.