Poll Everywhere welcomes Dr. Carmen Simon as the guest author of this series on creating better PowerPoint presentations.
Dr. Simon is a cognitive scientist, a leader in the virtual presentation movement, and an internationally renowned public speaker. She’s also a founder of Memzy, a worldwide presentation consulting firm. This is part one (including study background) in a series based on her research published in 2013.
I recently completed a study examining the intersection of cognitive psychology and communication from the perspective of PowerPoint. I was motivated to carry the study because I noticed three trends in the past decade:
>> A dichotomy in information processing habits: we crave information (spending 60+ hours a week online consuming content), but we also grumble about how we’re overwhelmed by so much information.
>> Ubiquitous use of PowerPoint for information processing: particularly as a standalone offering. A quick search through Slideshare.net confirms the growing trend of on-demand PowerPoint presentations.
>> PowerPoint-based presentations that look very similar: making it more difficult for messages to stand out. How many presentations have you seen lately where either you can’t remember who created them or they looked similar to something else you saw months ago?
These observations invite the question: how does one distinguish a particular on-demand PowerPoint presentation, given existing informational noise and competition?
1,540 subjects participated in the study, where I started with a very basic question applied to a very basic on-demand presentation: How many slides does a viewer remember, on average, from a text-only, standalone online PowerPoint presentation containing 20 slides?
To answer this question, I used the isolation effect theory, according to which, items (in this case slides) that stand out in some way from a homogenous list have a higher likelihood of being recalled.
1. Participants remembered an average of four slides from a 20-slide, standalone, text-only PowerPoint.
2. Neutral visuals helped, but didn’t change the rule of four. There was a statistically significant difference between the recall of content in text-only slides versus slides that contained text and neutral visuals. However, the recall rate did not exceed four slides in any of the 26 PowerPoint deck manipulations included in the study.
3. Participants tended to remember the same content and not slides at random, as was predicted. This means that it may be possible to control what people remember by using a certain set of criteria.
4. Five is an important number. Applying the isolation effect every nth slide (3rd, 4th, 5th) did not impact the overall recall of an entire deck. However, when a change was made every 5th position (slides 5, 10, 15, and 20), those slides tended to be remembered better than any other randomly selected slides from that deck. The reverse was true for slides changed in every 3rd and 4th position.
These findings can be linked to a set of practical and immediately transferable guidelines for anyone who creates on-demand presentations. Let’s start with the first one:
Part one: The magic number four
No article on memory capacity and short-term memory can escape without quoting cognitive psychologist George A. Miller. Miller contended that there’s a limit to the number of items the working memory can retain: 7 ± 2.
Other researchers have since questioned the limitations of memory capacity, suggesting that the new magic number is 4 ± 1, and that people form clusters of no more than three or four items to recall. When memorizing lists, some researchers observed that items in a list entered a fixed-capacity rehearsal buffer and displaced a randomly selected item already there, when the capacity of approximately four items had been exceeded.
Newer research suggests that the capacity for visual working memory is limited to four items. In a “list” or 20-slide PowerPoint, if information after four slides starts to be displaced by other items that were just viewed, it makes sense that the average recall rate would be four slides from the entire list.
The good news is that, if we know that the amount of slides people remember is limited, we don’t have to try so hard on every single slide we present.
Let’s test what you’ve learned: Which is better?
Even though this study was created in an on-demand setting, let’s reflect how this would apply in a face-to-face setting, where a presenter is involved.
Imagine someone had to present the deck below. Can you sense how everything is so intense on every slide, and how each slide may have taken a long time – and quite a bit of money – to develop?
On the opposite end of the spectrum: can you tell how weak the content is in the example below, where someone did not take that much time to place text in a sequence of slides?
So, which deck is better?
Surprisingly, while both examples may have good content, they are equally bad where memory is concerned. This is because when everything is equally intense or equally weak, something has to give.
In an environment where there is a presenter, the content has a chance because the presenter can do something to deviate from sameness – such as inviting participants to answer questions, participating in a group exercise, or switching from PowerPoint to a software demo.
In an on-demand situation, the slides are all you’ve got. How do you control which slides people remember?
Part two: Can you control what people remember from PowerPoint?
The study results showed that approximately 1,500 people tested remembered slides according to a pattern. Here’s the content included in the slides that people remembered more frequently:
- Slide 6: Don’t wear stripes because they dance around on the screen and are distracting.
- Slide 7: Don’t wear white. It glows and it becomes the most noticeable thing on the video screen.
- Slide 8: Pastel shirts work well on video.
- Slide 9: Don’t wear black, it is too harsh and can suck up all the light.
The purpose of this article is to show you how you can influence what people remember. Use these characteristics next time you’re creating a presentation.
Concrete visual language
Participants in the study tended to remember the same slides even though those slides did not contain pictures. This may be because the text was highly visual, in the sense that it generated mental pictures (e.g., Don’t wear white, black or stripes).
This observation matches research from advertising, according to which high-imagery words are remembered a lot better than low-imagery or abstract words.1 This is great news because many presenters complain that they do not have time or money to find and purchase expensive images for all slides in their decks. If you have highly visual language, you can save on other resources.
Visual language is typically concrete language. In general, concrete words are easier to remember than abstract words because concrete labels can be encoded in two separate ways: one involving an image and the other involving a verbal code or meaning. In the example below, notice how the concrete words are easier to remember than the abstract ones:
Dare to insert text-based slides in your presentation, with the condition that people can picture that text without much mental effort.
The four frequently recalled slides can be “grouped” around the same topic: what to wear and what not to wear.
People remembered these slides in the conditions where slides were shuffled, so the slides above did not appear in sequence. Slides with tight links are remembered more than slides with weak links. For your next presentation, wonder how easy it would be for viewers to identify a few groups (preferably no more than three) in your presentation. Sometimes, the error that people make is to provide too many groups or not specify how slides relate to a certain group.
Color coordination can often help group slides together. Notice how in the example below, there are four sections, each indicated by its own color:
The cautionary part about using colors to group slides in a presentation is that memory works on a chaining mechanism. The recall of an item depends on its predecessors, and items that appear later in the chain (or slides that appear later in a presentation) depend on the accurate recall of previous items. While color helps with chunking, it may not provide a link that is strong enough between various items.
For your next presentation, ask this question: If I asked viewers to relate slides at the end to slides at the beginning, would they be able to easily form a connection?
Endings are often rushed. Presenters run out of time, and often there is more emphasis on particular content than on connections between different parts of the presentation. Keep in mind that connections between content parts are just as important to memory as discussing individual content parts. Each time you introduce a new content piece, ask: How does it integrate with everything else?
Participants in the study who identified as novices in the topic of webcasting (the content for the presentations they were asked to remember), tended to remember more slides than those who considered themselves experts.
This may be explained by looking at a psychological construct called schemas – cognitive frameworks that help us organize and interpret information around us. Schemas influence the way new information is processed and they guide our expectations of what should occur. When information deviates from existing schema, attention is enhanced, which may lead to better recall.
Research in advertising hints at a similar fact: viewers exposed to unfamiliar ads engage in more extensive processing, and those exposed to familiar ads are less engaged and involved in more confirmation-based processing.
Sometimes experts “brush over” information thinking they already know it, and therefore not much is retained. If you want your presentation to attract attention, find out what your audience would consider novel. A thorough audience analysis can be revealing.
This was another trait shared by the four most-recalled slides. The word “wear” was repeated several times, such as in what to wear or not to wear.
Linking this to the idea of clustering: research suggests that, during recall, words that are repeated along some dimension are recalled successively.2 Practically speaking, it may be beneficial for content designers to use similarity of items that are important in a presentation to be recalled.
The example presentation below shows how words such as “RPM”, “Revenue”, and “Revolution” are repeated on a few slides, making these terms more likely to be recalled later:
Another characteristic of the four popular slides is that they contained negative information (e.g., Don’t wear stripes. Don’t wear white. Don’t wear black).
Several other researchers contend that negative information is more memorable in the sense that people tend to remember more details.3 This may be because the right fusiform gyrus – a region in the brain responsible for processing exemplar-specific details – displays higher activity during the successful encoding of negative objects.
If recalling details is important to you, then expressing content in negative terms may be worth considering. If remembering the gist of the information is sufficient, then positive content is suitable.
Slides that reported a high recall in the study were slides that offered advice that made the viewers “look good” (e.g., Avoid wearing white, black, or stripes in a webcast. Wear pastels). In a society that craves portraying positive images, it is understandable that ego-enhancing content attracts additional attention – which may translate into improved recall.
Notice in the example below how the self-boosting messages – paired up with concrete words – may lead to attention and improved recall. We will quiz you next week to see if it worked.
Recommended stories for you:
1Unnava, H. R., Burnkrant, R. E., & Erevelles, S. (1994). Effects of presentation order and communication modality on recall and attitude. Journal of Consumer Research, 21, 481–490
2Howard,M.W., & Kahana, M. J. (2002). When does semantic similarity help episodic retrieval? Journal of Memory and Language, 46, 85–98
3Kensinger, E. A., Garoff-Eaton, R. J., & Schacter, D. L. (2007). Effects of emotion on memory specificity: Memory trade-offs elicited by negative visually arousing stimuli. Journal of Memory and Language, 56, 575-591