PowerPoint is Not as Good As you Think
Simple explanations from cognitive science
Several years ago, when I started my PhD program, I took a course given by the Mathematics department. When the teacher finished the introduction part, he started to write down notations and equations on the whiteboard.
To be honest, I was surprised for quite a while. For years, in almost all the lectures (including the ones I gave as a teaching assistant) that I attended, slides were used for lecturing and the whiteboard/blackboard is only an option for illustration once a while.
I began to recall all the math lectures that I had back in university, and I found out most of the math teachers prefer writing instead of replying on slides.
I guess they must have tried to use slides, and somehow it turns out to be not suitable, so they return to the old technique.
There must be something wrong with PowerPoint.
Let’s think about those great lectures that you attended and those great speeches in the history. Was PowerPoint applied there? If not, would it be helpful to have a better presentation?
What I can remember is that PowerPoint is never an essential part of those great presentations, and it is barely used actually. If used, just for presenting images or animations.
How about those terrible lectures?
Surprisingly, I found out that PowerPoint always play a role to be blamed there. PowerPoint can easily become messy once you see awfully organized words, images, pictures, formulas on it, perhaps with terrible formats. What’s worse, there is one person standing aside, bubbling about these messy stuff.
I am not the first person to blame PowerPoint.
“Many, many years ago, we outlawed PowerPoint presentations at Amazon,” Bezos said at the Bush Center’s Forum on Leadership in 2018. “And it’s probably the smartest thing we ever did.”
There is even a Swiss political party called Anti PowerPoint Party (APPP) that is dedicated to decreasing professional use of Microsoft PowerPoint and other forms of presentation software. This party claims that “PowerPoint causes national-economic damage amounting to 2.1 billion CHF annually and lowers the quality of a presentation in 95% of the cases”.
So, what’s wrong with PowerPoint?
My answer is
PowerPoint is a powerful for presenters, but terrible for listeners.
As a presenter, PowerPoint is a great tool as a reminder. You don’t need to remember too many details of the presentation, as long as you have decent slides. However, for listeners, slides causes distraction and confusion and thus prevents us from understanding the presentation normally. The reason behind this is:
We cannot read, listen, and think at the same time.
To further understand this, we need some knowledge from cognitive science.
When we are trying to understand a presentation or any other content, we are actively using our memory system. Our memory is capable of doing lots of fascinating things, but it also has lots of limits.
In fact, the human memory system consists of two parts: short-term memory and long-term memory. As its name suggests, short-term memory is the capacity for holding a small amount of information in an active state for a short interval.
For example, short-term memory holds the statistics stressed on the slides that catches your attention. What’s important is that the short-term memory has a limited capacity. At first, scientists speculated the capacity to be around 7 items, and later this number is reduced to be around 4.
The effect of this characteristic is that when we speak or think, we cannot consider too many things once at a time. If that number goes beyond the limit, we become overwhelmed and confused.
This works for both the speaker and the listener. The speaker is not able to release too much information and the listener is not able to comprehend all of them.
However, PowerPoint breaks this balance.
With slides, the presenter can easily prepare much more material and just refers to the slides once something is missing in his mind. This greatly increases the cognition load of the listeners since they did not access those material beforehand.
What’s worse is that no matter how well the presentation is organized, the presenter needs to repeat what’s already written on the slides. It means that listeners are fed with double the contents, and they have to read, listen and think at the same time, which is an unnecessary burden.
Take away lessons
- Next time you give a presentation, try to reduce the amount of information on the slides if possible.
- Carefully control the amount of new information that you release. It is better to play the slides line by line, or part by part, instead of presenting the overwhelming information at once.
- As a listener, try to focus more on listening and reduce “multitasking”. Only refer to the slides when necessary.
- Similar things also work for writing: just think about why good writers always start from stories instead of bringing up new concepts at the beginning…
Thanks for reading!
