the-online-scientist-blog-presentations-bandwidth-320If you read our blogs, you’ll notice that we talk a lot about making whatever you publish about science easy to understand. This may feel repetitive sometimes. And being scientists ourselves we get why you may think it’s the least important part of any presentation.
Facts are everything right? Well….not really. Facts are key, but if no one is able to reproduce what you’re saying, then all the facts in the world are not going to make a difference.
In short:

Facts + clarity = impact

To quench that thirst for a more in-depth explanation of that other side if the medal, here’s an entire blog devoted to why we think it is key to any talk, article or website to be easy to understand.

Introducing mental bandwidth

Every person, whether they’re old, young, rich, poor, man, woman, soldier or scientist, has a certain mental bandwidth. That bandwidth, like a talent, varies between people, but what doesn’t change is that it’s finite. And various things can take it up. When you have to keep track of a shopping list you are using bandwidth. When you have to remember until what time your parking meter has been paid, you are using it too. But it also works on a longer term: financial troubles or a sick child can take up a lot of bandwidth. And just like with an internet connection, trying to download too much at the same time will slow everything down.

If nobody can understand your message, no facts will make a difference in the impact you have with your communication!

Not all burdens are created equal

Some people are incredible at keeping lists in their head, while others find it easy to deal with insecure teenagers. In other words; not only is everyone’s ability to deal with things different, the burden that a certain task or event poses also varies from person to person.

This makes it very hard to predict how much bandwidth you can actually claim when you approach people with a subject. Whether it’s a presentation, a website or a worried patient sitting at your desk, you have no way of knowing what the capacity is that you can claim from that audience. To be sure that the message comes across, you should assume that that capacity is very small.

Try to minimize the mental capacity you claim, and use it as efficient as possible


It means that you need to be aware of the starting point of your audience. When delivering a talk on genetic engineering, do you start with CRISPR? Or with DNA? Perhaps you explain what a cell is, or maybe you take off at the dawn of farming. Knowing where to start is key. It will make sure the information builds on what your audience already knows (without being redundant).

Knowing where to start is key.

Having a clear story helps with this, because you create a framework for the listener that allows bits of information to easy fall into place. This takes up much less effort than when your audience has to pick up and look at every bit of info in their head and try to fit it in different places in the narrative. This takes up mental capacity that your audience needs to follow the next bit of story. Once they miss that, and when your story isn’t clear, you have lost them for the remainder of the talk. Find out more about how to write your presentation.

The same thing goes for unclear slides. If you present a slide with the fluffiest graphs and no conclusions, people will stop listening. They need to devote all their mental bandwidth to the ‘puzzle’ on screen. Not until they solve it and arrive at the conclusion of the graph will they direct their attention back to you. And that is assuming they arrive at the right conclusion. In other words: keep them engaged with what you are saying and just give them the conclusion. For more tips on creating crystal clear slides, read this blog on how 5 simple tricks can improve your presentation slides.

A good presentation can be followed by someone who’s also looking at their phone

To conclude…

Even if your audience is gifted, you never know what else is going on in their lives. Don’t claim more mental capacity than you need. If you buy a powerful laptop you’re not going to use Photoshop as a text editor just because it is able to, right? You still would use Word. (To take that analogy a little further; you do this because you never know what’s running in the background). Don’t turn your presentation into an IQ-test. Make sure your audience can easily grasp whatever you’re showing or telling them. This ensures that they have enough capacity on hand and don’t have to either zone out or trail behind.

Don’t turn your presentation into an IQ-test

Hopefully this helped you to realize a little why we hammer down on that comprehensibility message so hard. And yes, it’s hard work to make things easy! But from an economic perspective; it’s better that you put in that effort by yourself, than that you’re going to request that effort from all of your audience. If you have any questions or thoughts about this, let us know!