Mehrabian is often quoted as saying that the meaning of a message is communicated by:
- Your words 7%
- Your tone of voice 38%
- Your body language 55%.
This interpretation of Mehrabian has been comprehensively debunked many times, but still it persists. In this post, I’m going to:
- Describe the experiments Mehrabian carried out, and
- Identify the limitations of Mehrabian’s research
The Mehrabian formula comes from two studies in nonverbal communication carried out by Mehrabian and two colleagues in 1967.
To summarize, Mehrabian’s studies asked participants to judge the feelings of a speaker by listening to a recording of a single word spoken in different tones of voice.
Yes, one single word.
In the first study, the participants had to rate the feelings of the speaker after listening to each of nine different words. The words spoken were often inconsistent with the tone of voice used. For example, the word “brute” spoken in a positive tone. Each time they had to make a rating just on the single word they had listened to.
In the second study, only one word was used. It was chosen to be as neutral as possible: the word was “maybe”. They listened to a recording of the word “maybe” said in different tones and at the same time were shown photos of different facial expressions.
It’s from these experiments that Mehrabian suggested – but did not prove – the formula. If you’d like more detail, I’ve described the experiments in more depth on this page: Mehrabian’s studies in nonverbal communication.
The limitations of Mehrabian’s formula
Mehrabian has himself attempted to limit the application of this formula:
Please note that this and other equations regarding relative importance of verbal and nonverbal messages were derived from experiments dealing with communications of feelings and attitudes (i.e., like-dislike). Unless a communicator is talking about their feelings or attitudes, these equations are not applicable.
In a personal email to Max Atkinson, reproduced in Max’s book “Lend me your Ears” Albert Mehrabian said:
I am obviously uncomfortable about misquotes of my work. From the very beginning I have tried to give people the correct limitations of my findings. Unfortunately the field of self-styled ‘corporate image consultants’ or ‘leadership consultants’ has numerous practitioners with very little psychological expertise. (31 October 2002)
So if we limit the formula to the specific conditions of the experiments, it is only applicable if:
- a speaker is using only one word,
- their tone of voice is inconsistent with the meaning of the word, and
- the judgement being made is about the feelings of the speaker.
In other words, in the real world, Mehrabian’s formula is almost never applicable.
What do other researchers say
Mehrabian’s findings were frequently discussed in the psychological literature on nonverbal communication through the 1970s and 1980s. Researchers have made the following critiques of the methodology of his studies:
- They only used two or three people to do the speaking for the experiments.
- They take no account of the extent to which the speakers could produce the required tone of voice.
- They were artificial situations with no context.
- The communication model on which they were based, has now been shown to be too simple.
- They take no account of the characteristics of the observers making the judgements.
- The purpose of the experiments was not hidden from the participants.
For more detail on these critiques go to Mehrabian’s studies in nonverbal communication and scroll down.
The importance of delivery
I’m not saying that speech delivery is unimportant – it is. I think it can have a large impact on the credibility and persuasiveness of a speaker. I also consider content to be critical to credibility and persuasiveness. But I don’t think that their respective influences can be reduced to a formula.
Campaign to “Stop the Mehrabian Myth”
The main group of people who have propagated the Mehrabian myth are presentation trainers, public speaking coaches and other communications consultants. As a presentation trainer, I’m embarrassed that these figures are still being trotted out on a regular basis, when there is no substance to their real-world application. It’s damaging to the credibility of the training industry.
I’m also concerned about the persistence of the Myth because of the impact on presenters:
- The Mehrabian Myth puts unwarranted pressure on people who are nervous about speaking. They’ve been led to believe that their delivery can make or break their presentation. This is just not true. If they prepare well-organized valuable content and deliver it at least adequately they are likely to get their message across.
- The Mehrabian Myth leads some “wing-it” presenters to under-prepare their content under the misapprehension that so long as they can deliver with energy and dynamism they’ll get their message across. Again, not so.
That’s why I’m starting the “Stop the Mehrabian Myth” campaign.
Stop the spread of the myth
Many presentation trainers and public speaking coaches are doing their bit to stop the spread of the myth. These are the ones I’m aware of who have posts about it:
Max Atkinson – Body language and nonverbal communication (Max has a brilliant cartoon demonstrating the absurdity of the myth)
Jon Thomas – Mehrabian’s rule and the puzzle that is presenting (I like this way of putting it “In whatever bubble that experiment took place in, I’m sure his findings were appropriate. We don’t live in that bubble though, at least not in respect to presentations. “)
Presentation experts against the myth (without a current blog post):
What can you do
If you come across a blog post or article on the internet which quotes Mehrabian’s formula as if it were true, comment on the post or write an email to the author. If you don’t have time to go into detail, just refer them to this post.
When you’re speaking with colleagues, should the myth ever be quoted, speak up and let people know the Mehrabian myth is false.
Write a post with your views on the Mehrabian myth, and let me know so that I can link to it.
Deliver a speech on the Mehrabian myth to your club.
Update: I’ve written an extra post to respond to a secondary misinterpretation of Mehrabian that has come through in the comments: The secondary misinterpretation of Mehrabian’s research