GUEST POST: Multimedia Learning -- Back to the Drawing Board?
By Logan Fiorella
Logan Fiorella is an Assistant Professor of Educational Psychology at the University of Georgia. He is interested in how to help students apply what they have learned to new situations. His current research focuses on generative learning strategies, learning from examples, and the design of multimedia lessons. He is co-author (with Richard Mayer) of the recent book, Learning as a Generative Activity, which reviews the research evidence for eight strategies that promote meaningful learning. You can find him on Twitter at @Logan_Fiorella, and on his UGA faculty webpage here
How do you present visuals such as diagrams, charts, or graphs to your students? Perhaps you follow the contemporary approach by displaying a diagram on a PowerPoint slide and explaining what's shown on the slide. Or maybe you prefer the "old-school" approach and explain the diagram while you’re drawing it on the board ("chalk-and-talk"). Most of us likely make this decision based on personal preference, convenience, or intuition – yet it turns out these two approaches may actually differ in their impact on student learning.
According to the cognitive theory of multimedia learning (1), lessons should help students mentally integrate the instructor's words with corresponding graphics. For example, it's generally a good idea to use cues such as arrows or pointing to direct students’ attention to the relevant parts of a diagram, to avoid making students shift their attention between multiple visuals, and to synchronize your explanations with your graphics. Yet with PowerPoint, these guidelines are difficult to follow. After all, the instructor and the visuals are in two different places and the entire diagram typically shows up before we've started our explanation. By contrast, in the old-school approach our hand might serve as an attention guide, and the act of drawing might allow us to more precisely integrate what we're saying with what we're showing.
Richard Mayer and I tested this idea empirically in a recent study (2). In addition to seeing whether students learned better from seeing the instructor draw, we were also interested in whether any benefits of drawing were influenced by the visibility of the instructor's body or hand during the lesson. This is not only an intriguing theoretical issue, but it's also a common practical consideration for designers of video lessons, such as the highly popular Khan Academy videos and the trendy animated whiteboard videos (such as the one Memorize Academy made in collaboration with the Learning Scientists about how to study).
First, we randomly assigned college students from the University of California, Santa Barbara to watch different versions of a short, narrated video explaining how the Doppler effect works. Each lesson contained diagrams presented on a whiteboard depicting basic characteristics of sound waves and how the perceived pitch of a sound changes as a sound source (e.g., a fire truck with a blaring siren) approaches and moves away from an observer. Students who didn't see the instructor draw the diagrams instead viewed the exact same already-drawn diagrams throughout the lesson. Viewing already-drawn diagrams was our approximation of PowerPoint that was more similar to drawing diagrams in order to avoid confounding variables, such as the presence or absence of technology or the visual appeal of PowerPoint vs. drawings. After watching the lesson, all students answered questions that asked them to apply their newly acquired knowledge to new situations, like coming up with ways in which the Doppler effect might be experienced more intensely by an observer.
In the first experiment we ran, the instructor's body was visible throughout the lesson (images 1-2).
Image 1: Draw group
Image 2: Control group
When the instructor's body was visible, we found that students who had low prior knowledge of physics learned better from watching the instructor draw the diagrams by hand than viewing the same already-drawn diagrams. It didn't appear to help students who had relatively high prior knowledge, which was not especially surprising, given that additional guidance does not always help students who already have some of their own knowledge available to make sense out of the lesson (see, for example, the expertise reversal effect, (3)).
This initial finding was promising, so we took a closer look by "zooming in" on the lesson to focus on only the instructor's hand (images 3-4).
Image 3: Draw group
Image 4: Control group
With only the instructor’s hand visible in the video, we again found that students learned better from watching the diagrams being drawn, though this time it actually appeared to benefit students with relatively low and high prior knowledge equally. The effect among students with high prior knowledge could be due to a number of differences between the lessons in the two experiments (e.g., camera viewpoint or instructor presence) that can be addressed in future studies. However, our next focus was to address the intriguing question of whether the vicarious drawing effect is due to merely seeing the lesson drawn out in real time or if there was something special about seeing the instructor’s hand.
Now students saw a video of the diagrams being drawn without the hand visible (i.e., by viewing a recording created by drawing on a tablet computer; images 5-6).
Image 6: Control group
Image 5: Draw group
Image 5: Draw group
Image 6: Control group
This version of the lesson (diagrams being drawn without the hand visible) actually turned out no better than viewing the already-drawn diagrams. Does this mean that the instructor's hand is the driving force behind the vicarious drawing effect? Possibly. But since we didn't directly compare 'hand' and 'no-hand' instructor-drawn diagrams in the same experiment, our data don't quite allow us to go that far.
Taken together, this set of studies provides some encouraging initial evidence that drawing on the board does benefit students in some situations, likely in part because it better adheres to basic cognitive principles of how students learn from multimedia. That is, watching diagrams being created helps students better package the words and drawings into a coherent mental representation (or "mental model") that students can then use to solve new problems. For instance, in our study, students could better connect the instructor's explanation of how sound waves get compressed as a sound source approaches with the relevant parts of her drawings showing sound waves bunched up next to each other. This study also raises an open question regarding whether the instructor's hand provides a critical cue. Indeed, basic research suggests that hands do tend to be attention magnets (4).
Of course, we should be cautious about deriving instructional principles based on short lab-based experiments covering a single topic. The effects found were also relatively subtle, suggesting one might wish to look for additional ways to further improve the presentation of their visuals (1). Nonetheless, teachers may find it worthwhile to occasionally consider shutting down the PowerPoint and going back to the drawing board with old-school chalk-and-talk.
(1) Mayer, R. E. (Ed.) (2014). The Cambridge handbook of multimedia learning: 2nd ed. New York: Cambridge University Press.
(2) Fiorella, L., & Mayer, R. E. (2016). Effects of observing the instructor draw diagrams on learning from multimedia message. Journal of Educational Psychology, 108, 528-546.
(3) Kalyuga, S., Ayres, P., Chandler, P., & Sweller, J. (2003). Expertise reversal effect. Educational Psychologist, 38, 23-31.
(4) Reed, C. L., Jefferson, D. G., & Steele, C. (2006). Hands up: Attention prioritization of space near the hand. Journal of Experimental Psychology: Human Perception and Performance, 32, 166-177.