Visual aids in teaching – how to avoid Death by PowerPoint
Why do we keep making bad presentations that even we ourselves find annoying? And why do we put so much effort into our academic work, but the minute we have to make a presentation, we simply throw it together on autopilot? And is there anything we can do about this? Tarald L. Berge will give us the dos and don’ts of PowerPoint.
Visual aids in teaching
There are two reasons that I wanted to talk about visual aids in teaching, which have bothered me ever since I first came to Blindern. Why do we keep making such bad presentations that even we find annoying? And why do we put so much effort into our academic work, but the minute we have to make a presentation, we simply throw it together on autopilot?
I am going to address these issues by talking about three things. (I) What do we know about the learning impact of PowerPoint? (II) The first question we should ask ourselves as we prepare for a lecture or seminar is: Why use PowerPoint? (III) And if we are going to use visual aids like PowerPoint: What is the best way possible to use it?
- See the PowerPoint presentation from the teaching forum.
- For tips on using visual aids in teaching, see Simen S. Solbakken’s presentation.
- Visual aids in teaching
- HOW? – Five principles
A lot of what I am going to talk about today relates to a single, fundamental question: How does our concentration work? As professional communicators, we ought to be interested in how we can help the students concentrate during our lectures. We ought to care deeply about how much of what we are trying to convey to them they actually take in. And how much they understand.
The most important thing I can tell you about our concentration is that it is very bad, and we are very easily distracted. This is why our widespread use of visual aids like PowerPoint, which is the norm today, often serves to inhibit learning rather than promoting it.
So what kind of PowerPoint presentations am I talking about? Let me show you a slide I used in a seminar this autumn:
Figure 1 – A fairly typical lecture slide
If you have used a slide like this in your own teaching, then I would like to make you aware of two statistics: If you have a slide like this on the screen behind you while you are lecturing or holding a seminar, there is a 90 per cent chance that the people you are talking to will have forgotten what you said 30 seconds after you said it.
This is linked to the way our working memory (i.e. short-term memory) works, and how difficult it is for us to store the information we put in it. Let me give you another example to emphasise how easily our brains are distracted. Imagine you are at Oslo Central Station and have bought a train ticket from the ticket machine. From the time you bought the ticket until you sit down in your seat, most people will have checked the carriage and seat number an average of six times. That’s how bad our working memory is at remembering things. And the bad news for us is that our working memory is the same, whether they are buying a train ticket and or sitting in a lecture. We are easily distracted, and we forget very quickly. Especially if we overload our working memory with too much information at once.
John Medina, one of the world’s leading molecular biologists, famously said: “If companies have as little respect for business as they have for presentations, the majority would go bankrupt.” I have worked in the private sector for several years, and I couldn’t agree more. However, I would venture to claim – and it is possible I am exaggerating a little now, that the university sector is even worse than private companies in this respect. Given that one of our two core activities is dissemination, this is not ideal.
What do we know about the learning impact of PowerPoint?
Pedagogy and learning sociology provide us with two types of studies. There are studies focusing on the students’ and teachers’ own perception of PowerPoint usage, and there are studies that look at observed learning effect.
Experienced learning effect
The people who investigate students’ and lecturers’ own perception of the use of PowerPoint in lectures are cautious optimists. Students generally say that they prefer PowerPoint in the lectures they attend. What they are actually saying is that they prefer PowerPoint because it makes it easier for them to take notes, and because it creates a more exciting learning space.
Lecturers are a little more sceptical. Lecturers who use PowerPoint in their lectures are divided, while lecturers who don’t use PowerPoint stress that they find that speaking without visual aids ensures more interaction with students.
Observed learning effect
By contrast, people who investigate the actual learning effects of the use of PowerPoint in lectures are more pessimistic. Basically, there is no demonstrable learning effect of using PowerPoint in the teaching situation – in either single point studies or time series studies. The ability to understand complex things does not increase, nor is it possible to identify any discernible effect on students’ ability to remember larger volumes of information in a lecture with PowerPoint, compared with a lecture without PowerPoint.
Critics highlight a couple of interesting aspects.
Should we hand out lecture notes before or after a lecture?
The first concerns the practice of handing out lecture notes before or after the lecture. Students who are given the lecturer’s notes take far fewer own notes. And we know that taking notes leads to deeper learning than merely listening. At the same time, continuously taking notes helps students sort and organise their knowledge there and then.
Bullet points can trivialise knowledge
The second aspect concerns the built-in structure of PowerPoint, i.e. the bullet point list. This way of condensing a lot of information has a tendency to trivialise knowledge. Many students perceive the lists as exhaustive and assume that the perspectives are more mutually exclusive than they actually are.
PowerPoint may lead to less interaction
The third aspect is that PowerPoint seems to lead to less interaction between the students and the lecturer. We know from pedagogy that people learn best in interaction with others. They need to feel that they are interacting with the person they are listening to. This does not necessarily mean that teachers must strive to be in actual dialogue with the students during a lecture, but by using a conversational tone and making eye contact, the lecturer can create a perceived interaction. Two things tend to happen when we use PowerPoint:
The first is that we start talking to our presentation, instead of addressing the students. We turn to it frequently to make sure we have covered everything we have said we would talk about. And we are often more focused on the flow of the presentation than the audience’s response.
The second thing that happens is that the students’ focus is drawn towards the screen, and away from the lecturer. We behave more like we do at the cinema – we stare at the screen, and the lecturer becomes a small commentator down in the corner. I will talk about how we can avoid this a bit later on, but it is important to bear this effect of PowerPoint in mind.
So, we have ascertained that it is very uncertain whether there is any empirical advantage to using PowerPoint in teaching. And yet the vast majority do. Why is this so? Well, as I mentioned at the beginning, I think it is because many of us act on autopilot and follow precedent. It has become the norm that you have to have presentation material behind you when you talk, but very few people think about why they actually use PowerPoint.
Is your PowerPoint presentation your product?
It has become quite common for the PowerPoint presentation to be the product you create when you are preparing a lecture. Many people do not draw up a separate outline or manuscript. They make a PowerPoint presentation and then relate to it as they lecture. Here, there has been a subconscious shift in the transition from blackboard (or whiteboard) to PowerPoint. I have a question for those who have taught with a board: did you used to go into the auditorium and write out an entire outline of the lecture on the board before you began? Didn’t think so! Most people had an outline, and used the board to highlight important points, or provide a visual illustration where needed. However, in the transition to PowerPoint, these two products – that is, the outline and the illustration – have merged.
Create an outline for your lecture.
My first general piece of advice is thus: Make a clear distinction in your mind between your lecture as it appears in your outline and the visual elements you want to use. And always make the former first. In this context, you may want to ask yourself the following questions after having prepared the outline: Why am I going to use PowerPoint in this lecture? To answer this question, consider the following. PowerPoint can be very useful for some things.
Use PowerPoint to create visual hooks
The first thing you can use PowerPoint for is to create “memory hooks”. We know from memory research that visual hooks make it easier to remember large volumes of information. If you can remember the hook, you can deduce what was hung on it.
Use PowerPoint to illustrate relationships and clarify complex ideas
The second thing PowerPoint is very good for is illustrating the correlation between elements or events. Used correctly, PowerPoint can help clarify complex concepts and create key points in a long narrative.
However, if you do not have a clear idea why you need a PowerPoint presentation, then don’t use PowerPoint at all!
HOW? – Five principles
If you decide that you are going to use PowerPoint, there are a few simple design principles you can apply to ensue your presentation is as learning-friendly as possible.
I will now run through five general design principles that will help optimise your presentations both cognitively and psychologically.
And let me stress here, we are not talking about creating an audiovisual extravaganza. The focus is on ensuring learning – as opposed to distraction. We want to use PowerPoint as an aid to learning. It should support what you say, not draw attention away from it. And it should help your audience understand the complicated parts of your lecture.
Applying these principles may force you to think a little differently than you have in the past – but this does not necessarily mean more work. On the contrary, I think using these principles makes it easier to create presentations.
1) Only one message per slide
The first design principle is about how many points or elements of substance we cover per slide. When you pull up a slide, like the one above, the following happens: Your students stop listening to you until they have finished reading the slide. The more points they have to read, the more of what you say they miss. This means that what was perhaps a well-constructed, interwoven narrative becomes broken up. If you have 30 slides in your presentation, most students will have 30 gaps in the story you have told them. And the more there is on each slide, the bigger these gaps will be.
So make it easy for your audience. My first principle is thus: Have only one message or element of substance per slide. We have a very limited ability not to have our focus drawn to what appears before our eyes.
2) Do not use whole sentences in your presentations
The next design principle concerns the way our brains (or more precisely our working memory) works, and the use of sentences in lecture slides. This principle is built on John Sweller’s cognitive load theory and an effect in our brain called the “redundancy effect”. Put very simply, the redundancy effect means that if we get the same message through multiple channels, at the same time, then our memory breaks down. And we don’t remember anything at all!
Cognitive load researchers often talk about the double fallacy, which means the same message being given in the same form in two different channels at the same time. We often commit a triple fallacy, by handing out lecture notes before lectures in addition to showing them on the projector and providing the information orally. It is therefore important that what you say and what is on your slides are not the identical. This is why it is a bad idea to use whole sentences. If you have whole sentences in your presentation that the audience is looking at while you are talking, the audience probably won’t hear any of what you are saying. The thing is, they can always go back and read the slides later. But they can’t usually go back and hear what you said again afterwards. And in this case, what is the point of lecturing?
So, what should you do? Move long sections of text down into the comments section below your presentation – where it can function as your own presentation notes – and keep only the main points or memory hooks in your presentation. Again, separate what you are going to say (your outline) from what you want to illustrate this with (your presentation). Principle number two is thus: Do not use whole sentences in your presentations.
3) Make the most important element on your slide the biggest
The third design principle has to do with the size of the writing and objects in your presentation.
First, let me make you aware of one thing. Each time you open your eyes, they automatically look for one or more of four things:
- moving objects
- objects in signal colours – i.e. red, orange or yellow
- objects with high contrast
- large objects
This is coded into our brains genetically as a safety mechanism. So how can we make use of this knowledge?
First let’s look at the way the human eye is naturally drawn to large objects. Take another look at the slide above. What is your eye drawn to? The heading (and the Le Monde Diplomatique logo). But how often is the heading the most important thing on the slide? Very rarely. Nevertheless, PowerPoint templates always have a large heading. An added problem is that most of us are very used to using headings when writing articles.
The important thing here is to realise that PowerPoint presentations are not built according to cognitive design principles. And presentations are not articles. The third design principle is thus: Make the most important element on your slide biggest
4) Use animations and a dark background
The fourth design principle concerns contrast.
As mentioned, contrast attracts focus. How can we use this to our advantage? You can use a very simple, built-in feature in PowerPoint: animation [see the example in the presentation]. In this way, you can steer the focus of your audience to what you are talking about at any given time.
Another contrast issue is linked to another PowerPoint default: The background colour. We routinely force students to sit looking at a glaring white screen in lectures. In addition to drawing focus away from the content of the lecture (i.e. you) and towards the visual aid (the presentation), it is very tiring for the eyes to sit staring at a bright white screen for two hours.
So unless you want to teach wearing bright signal colours or like to run around on the podium waving your arms about, I would recommend using a dark background in your presentations, so that students look at you. Give their eyes a break. Make yourself the centre point of the presentation, and let PowerPoint be an aid.
The fourth design principle is thus: Use animations and a dark background in your slides.
5) Maximum of five or six objects per slide
The last design principle is about the ideal number of objects per slide.
We are unable to process more than five or six elements at once as a sensory impression. Then we have to read or count [see the example with the white balls from the presentation].
The cognitive exercise of counting takes 500 per cent longer than a sensory impression. And when you are counting, or even worse, reading – then it is quite difficult to pay attention to what is being said in the background at the same time.
The last design principle is thus: Never have more than five or six objects on the screen at a time. If you have more than that on the slide, people will spend 500 percent longer orienting themselves in your slide, and we know that during that time they will not manage to listen to you at the same time.