Whether we like it or not everyday speech is filled with unwanted “ers” and “ums”, hesitations and pauses. We can often feel negatively about these interruptions to the smooth flow of speech and there are whole web articles giving tips on how to avoid saying “um”. You might think that such additions to speech make it more difficult to follow what the speaker is trying to say. However, surprising research has shown that we should perhaps change the way we think about these “ers” and “ums”.

ellie_author_templateenWe call these interruptions to the flow of speech disfluencies. Surprisingly, research findings have recently contradicted our negative attitudes towards disfluencies. Instead of hesitations in speech impairing our understanding of what is being said – as many people may believe – it has been found that we are actually better and faster at remembering what has been said after an “uh” or an “um” in speech. So it seems that our brains are processing information better after hearing a disfluency in speech.

In fact, by recording brain activity, researchers have shown differences in brain responses to words spoken after an “uh” compared to when the same sentence was spoken without an “uh”. What we would like to know is how the information is being processed differently by the brain.


An ongoing debate between researchers is the question of whether improved processing is due to our brain having more time to process the information, or due to the hesitation capturing our attention while we wait to hear what the speaker will say next. This is one of the questions that we are trying to answer.

Don’t stop your “ums”, disfluencies support successful communication!

Another possibility is that hesitations change the way we process what is being said by changing what we think and predict the speaker will say next. One way of looking at people’s predictions about what will be said next is by measuring where they are looking with an eye tracker. With an eye tracker we can tell where a person is looking in the environment or on a computer screen. By recording a person’s eye movements to pictures while they listen to sentences, we can tell what that person thinks will be said next. This is because a person’s eyes will move to look at the object that they predict will be mentioned before it has been spoken. From this type of experiment, it has been shown that hearing an “uh” changes our predictions about how a sentence will end. For example, if we hear an “uh”, we will predict that the object mentioned after the “uh” will have a more unusual name. Or we might predict that the speaker is about to introduce a new object into the conversation, rather than mention an object that has already been spoken about. It’s thought that this is because a hesitation signals to the listener that the speaker is finding it more difficult to retrieve the next word from their memory.

So it seems that our brains are processing information better after hearing a disfluency in speech.

While we shouldn’t start to include “ers” and “ums” in our speech on purpose, we should change the way we think about hesitations in speech. Instead of feeling negatively about “ers” and “ums” and trying to eliminate them from our speech, perhaps we should accept them and see what they can teach us about how our brains process speech.


Featured image: Jacob Botter (flickr)