Imagine that you’re in a restaurant, at a long table with a group of friends. You’re seated in the middle, and conversations are flowing to your right and your left.
Now imagine that you’re taking a class, watching a presentation. The instructor has bullet-points up on the slides and is lecturing on the topic du jour.
What do these two scenarios have in common?
At first glance, not a lot. In one case, you’re straining to follow the threads of conversation. You may feel a bit like a tennis ball, bouncing back and forth between discussions.
In the other, you’re able to focus on the matter at hand. There’s one speaker, one discussion, one topic.
According to a recent paper, ‘The Neuroscience of PowerPoint(tm)’ by Jared Cooney Horvath, though, these two scenarios have more in common than you might think:
Both make it incredibly difficult for you to follow what’s going on, comprehend it, and remember it later.
Which means that all that hard work you’re putting into your PowerPoint slides might hinder your students’ ability to get results, instead of helping them.
Curious? Read on for more of what Horvath’s article reveals.
Our Brains, the Highways
To understand what’s going on, we need to first look at how our brains process information.
Think about your neural pathways as if they were highways. Auditory information flows along one highway, visual along another, and so on.
So long as you’ve just got one flow of information along each highway, things will keep moving along.
But what happens when you need to process two flows of information at once, along the same stretch of road? You get, in effect, a merge lane. The car that was in front of you before you merged might now be 4 or 5 cars ahead. It’s no longer a nice, organized flow.
The same things happen in our brains. When you have one flow of information along each pathway, it works great; the information flows along. But as soon as when you try to have many flows of the same type of information, such as several conversations at once, it’s more like a merge lane onto the highway: everything gets jumbled up and mixed together.
That’s why we can’t listen to two conversations at the same time. You can either focus on one and get none of the other (like letting all the traffic pass, before you try to merge), or you can try to pay attention to both and get less out of each.
Reading With Your Ears, Not Your Eyes
So far, this isn’t that surprising. But what is surprising is how the written word fits into this picture.
Instinctively, we might think that reading is a visual process. That’s why, for example, it’s common practice to reinforce your spoken presentations with bullet-point slides. As the thinking goes, this creates a better learning experience.
But in fact, most of us don’t process written information along the visual pathways. Instead, our brains process words as auditory information, using the auditory pathways to comprehend and remember them.
This means that listening to a speaker and reading the text on their slides is more like trying to follow two conversations at once — and it has the same negative effects. Your ability to comprehend and remember goes way down as soon as you try to process both streams of information at once.
It’s not just neurology that leads us to this conclusion, either. Studies of students have shown time and time again that there is a marked decrease in how much you learn (both short-term and long-term) when the information is presented both orally and textually.
Here’s one example that Horvath cites:
Kalyuga, Chandler, and Sweller (2004) presented trade apprentices with purely text, purely auditory, or combined text/auditory instructions outlining varied technical processes (such as fusion soldering or drill speed measurement). Apprentices in the isolated instruction conditions learned faster and performed better (with the exception of a final multiple choice quiz) than apprentices in the dual condition.
Skip the Bullets; Now What?
So if we’re not supposed to use text on our PowerPoint slides, what should we be doing instead?
The obvious answer is to use images. And, indeed, the research bears this out. Images are not processed by the aural pathways; in fact, there are entirely separate areas of the brain that process images depending on what the image is of. When we see a face, for example, the facial recognition part of the brain lights up.
In other words, listening to someone speak while looking at related images is more like using two separate highways.
What the neuroscience doesn’t suggest, though, is that having the visual information makes the learning easier or better. In fact, quite the opposite. According to Horvath, we perform just as well with audio or visual information alone, as we do when it’s combined.
This leaves us in a bit of a connundrum:
If having text on our slides reduces comprehension and retention …
… and having images on our slides does nothing to help …
Should we just ditch the PowerPoint slides altogether?
The answer seems to be yes — unless you also do one, specific thing.
Right On Cue
What happens, for example, if you need to show a chart or a graph to make your point?
As we’ve seen, just showing the chart itself isn’t enough. But what does make a difference is when you use spatial cues — like circles, boxes, or arrows — to draw attention to specific parts of the image. Horvath cites many recent studies, each of which shows that drawing attention in this manner does trigger enhanced learning. In one case,
Direct cueing (via zooming) each step in-turn during an animation … enhanced learner comprehension and retention.
In another study,
Direct cueing (via colored highlighting) of specific aspects within a static diagram of a turbojet engine during an accompanying oral narration of how the engine works led to enhanced performance
In order to have this work, though, it’s important to also incorporate contextual cues. Simply put, when you use a different layout for every slide, your brain has to work overtime: not only does it have to interpret the information itself, it also has to figure out what to pay the most attention to.
Neurological imaging shows us that presenting images in a consistent, predictable manner ensures makes life easier for the brain. It spends less time finding and attending to the image, and more time learning how the image relates to what’s being said.
What Will You Do?
Look — I get it.
Buyers love video in their online courses. And so it’s become incredibly popular (and incredibly easy) to figure out some bullet points, put them on a slide, and then record a voiceover. Voila! Instant video.
I’ve done it myself.
But if nothing else, this latest neuroscientific research should give us pause. If nothing else, we ought to consider moving away from text-heavy slides, which get in the way of student results, in favor of image-based slides, which are essentially neutral.
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So now I want to hear from you. What do you think? Does this latest research change the way that you look at how you create your videos? Shout-out in the comments below.