How to use non-verbal communication for UX research?

Loïs Gauthier
March 2, 2023

Have you ever found yourself nodding or smiling during an interview/test because you were happy about a specific verbatim or feedback given by a user? Or on the contrary, raising an eyebrow or sighing for the opposite reason.

You probably realized the bias you were introducing in your research, but it was too late already.

We humans are meant to communicate our emotions and feelings in so many ways (verbal, paraverbal and non-verbal) that in the context of UX research, it feels very complicated to remain neutral.

Similarly, your participants’ non-verbal communication will provide extra info to be used in your analysis, creating more nuance and depth in your insights.

In this article we explore how to take advantage of non-verbal communication for UXR: controlling our’s as researchers and analyzing our participants’ to enrich insights.

communication vectors

Theory of human communication

There are many cues we use to convey meaning with our bodies when communicating with someone else. They fall into 3 categories: verbal, para-verbal and non-verbal communication.

Verbal communication is the actual words we use to articulate our speech. It is the most obvious form of communication. However, it only accounts for 7% of the message we convey to our interlocutor.

Paraverbal communication defines how you say the words: your tone, loudness, inflection, pitch, the use of pace and silence. It accounts for 38% of our communication’s perception.

Non-verbal communication englobes all the different ways our body accompanies our speech: posture, gestures, distance and use of space and facial expressions. It represents 55% of what our interlocutor will preceive.

Paraverbal communication

Pace and silence

Pacing and silence have as much meaning as the actual words they frame. They are the structure which reveals some of our internal state. The role of time in communication is called chronemics. This theory associates a different relationship to time to different cultures.

Here is a resource to dive deeper into this subject.

There is also a correlation between how fast someone talks and how comfortable they are: both extremes (very slow and very fast speech pace) can be attributed to nervosity.


If communication was a music score, paralinguistics would be everything on it aside from the lyrics.

We interpret these cues very naturally because they are part of our daily communication but a theoretical reminder can help create more consciousness about its mechanism.

  • tone and inflection: generally speaking, low tone fluctuations (monotonous speech) indicate a lower level of engagement
analysing paraverbal communication
  • loudness: the voice level used in speech varies widely across people (depending on how shy they are and if they are comfortable with speaking with you). A low voice can be a signal of low engagement, shyness or discomfort. These cues can be used to adapt your communication with UXR participants, make them more comfortable and thus more likely to share authentic feedback
  • pitch: aside from someone’s natural pitch, fluctuations of the voice pitch can reflect your participants emotions

All these tools can be used by participants to emphasize certain words, either positively or negatively.

average pitch for each emotion

Non-verbal communication


The degree of openness of someone’s posture is defined by the position of the spine, arms and legs in relation to one another. Bending the spine, crossing the arms or legs are considered closed positions. They can be interpreted as protection postures (protecting vulnerable parts of the body such as the throat, abdomen and genitals). These postures are related to unpleasant feelings such as hostility, disinterest or detachment.

Head and neck

Generally, uplooking angles of the head and neck reflect emotions of superiority (such as pride or self-assurance) while when they are tilted down, it can show emotions of inferiority. How the eyes follow these movements or not is an additional factor.

Arms and legs

Whether standing or seating, the position of the limbs can be yet another indicator of someone’s internal state. By scanning their position, you can assess their degree of comfort and adjust your own speech and body language to make them feel at ease if its not the case.

This contrast between postures is sometimes refered to as “high power” and “low power” body language. As there should be no domination interaction during a UXR meeting, as a researcher, avoid any of these positions expressing “extreme” openness or closedness.

Spine position

Other factors include inclination, orientation and similarity of the body:

  • inclination: leaning towards or inclining away
  • orientation: frontal facing or slightly at an angle, turned to the side or backwards
  • similarity: miroring other people’s body position can help connect with them and create more sympathy


Similarly to postures, gestures can be placed on a open/closed spectrum reflecting ones internal state. Generally speaking, outward gestures reflect an open posture.

Gestures can be categorized as speech related (they have a word translation and are usually culture related) or speech independant. This means some gestures are directly linked to what someone is saying and used to emphasize or clarify their meaning. Other gestures have inherent meaning and can be used without spoken language.

Distance and use of space

The study of the use of space in communication is called proxemics. In this context, horizontal space can be categorized into personal space, social space and public space. How close and comfortable people are to each other will define their relationship to space between them.

There is also a link between horizontal space and interpersonal relationships. In the context of UXR, researchers should aim at being on the same level as their participants to create trust and foster communication.

Eye contact

Also called mututal gaze, it has different factors: duration, frequency, patterns and blink rate.

The following can indicate disinterest, deceit or incomfort: eye aversion and high blink rate while frequent, longer eye contact and low blink rate can indicate comfort and interest.

Facial expressions

Facial expressions are universal and independant of someone’s cultural background. Studies suggest that even people who are born blind show the same facial expressions.

These facial expressions are particularly precise and diverse (more than 10 000 different micro-expressions).

In the context of UXR, you can use facial expression to assess how easily a participant answers a question or conducts a tasks.

Understand and control your non-verbal communication as a UX researcher

The first step to reduce bias caused by body language is to notice it. To do so, you can start by paying extra attention to the way you talk, move and react when interacting with other people. It applies outside of UXR too.

Then you can use some of the following techniques:

  • If you have some, explore existing video recordings of user tests/interviews you conducted. Except this time, your attention will be focused on yourself. Take notes and write down every element you notice about your tone and body language. If you don’t have any of these recordings, start making a habit out of it.
  • If you meet participants with your team, ask your colleagues for feedback about your body language. You can explain you are working on it and would like their honest feedback. This is especially relevant if you work in teams of 2 (a moderator and a note-taker).
  • In the meantime, you can record yourself talking or talk in front of a mirror to notice the way you express yourself.
  • Use silence and breathing to take a step back during an interview
  • Practice speaking slower and keeping your volume and tone stable to stay neutral

We know this is a hard exercise, try not to be hard on yourself and just noticing these opportunities for progress while giving yourself enough time to work on them.

Working on awareness to one’s bias before meeting a participant will also help prevent biased reactions. To do so, follow these steps:

  • Once your research question is ready, write down what you expect your participants to tell you, how you think they’ll react etc
  • Then, highlight the options that you would like better, those that would make your work easier or encourage actions you have taken

This should help you understand your bias and limit their expression during your meeting with participants.

If you do end-up expressing them, write it down in your notes and replay the situation in your head afterwards, trying to find a way you could have answered in an unbiased way.

To learn more about the different types of biases, read our dedicated article.

Use your participants’ non-verbal communication to enrich insights

Non-verbal cues can reveal participants’ level of comfort, their level of engagement, and their overall attitude towards the product or service being tested.

They can be used to detect situations in which a participant is expressing contrasting signals between their verbal and non-verbal communication. When this happens, it should be a signal that you have to dig deeper into this matter with your participant.

As a researcher, one should not use verbal or non-verbal communication alone to interpret a participant’s meaning: if you have doubts about what a participant meant because of non-verbal cues, use follow-up questions to confirm or invalidate your doubts.

A combination of both verbal and non-verbal cues with follow-up question is a best practice.

non verbal communication in UXR

In the context of user experience research, body language plays a great role in the way researchers present themselves and their study to participants and in the way participants react and give feedback.

If not used correctly, non-verbal communication (as much as verbal communication) can create extensive bias which in turn harm the objectivity of UX research.

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