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How to Incorporate Multimedia Learning in Didactic Sessions

Naomi M. Sell, MD, MHS, and Denise W. Gee, MD, FACS

February 1, 2019

Traditional teaching techniques may elicit images of a lecture in front of a chalkboard. In the life of an exhausted surgical resident, however, sitting in a chair and listening to a monotonous voice for an hour is more likely an invitation for sleep rather than an educational experience.

How, then, do we keep our residents and medical students engaged during didactics?

Multimedia learning not only keeps a listening audience engaged but results in better recall of the material presented.1 Multimedia education is the combination of words and graphics to promote learning. Examples include slideshow presentations, captioned videos, or handheld simulation devices. The utilization of multimedia, most often through programs such as PowerPoint

Recall Learning Theories

The ability to retain and recall information has been described in two theories: Dual Coding and Cognitive Load.

Dual Coding was described by Paivio et al. in 1971 and theorizes that our brains process information through two separate channels: a visual channel and a verbal channel.5 Each pathway is processed separately; however, studies have shown that information presented to both systems concurrently, as in multimedia presentations, has a higher likelihood of recall later.

Cognitive load refers to the amount of mental effort a learner requires to learn a topic. There are intrinsic and extrinsic sources of cognitive load.6 Intrinsic is the difficulty of the content in the lecture while extrinsic is the way the information is presented. We may not be able to control the difficulty of the content, but we can control how it is presented so that we can optimize it in a way that enhances learning.

With these two theories in mind, how do we best format our multimedia presentations for maximal resident benefit? Richard Mayer, PhD, has been a leader in the field of education theory and multimedia learning.7 His studies have illustrated key principles that will best serve our residents and students.

Principles of Multimedia Learning

Advances in technology have allowed for many audio and visual components to be incorporated in multimedia presentations. Unfortunately, not all charts or graphics are equally effective at promoting learning. Mayer describes 12 key principles for multimedia learning and how to best present content with the use of media agents.8 Studies of students have shown that PowerPoint presentations that utilize the following principles have better content retention rates and understanding of content:3

Coherence Principle

  • Exclude extraneous material that is distracting, such as words, pictures, and sounds
  • Avoid clip art that does not add to the knowledge at hand

Signaling Principle

  • People learn best when cued as to what the most important facts are
  • Signaling includes highlighting, an outline, headings, or arrows
  • Mention key facts multiple times to signal their importance

Redundancy Principle

  • Narration and on-screen text should not be exact duplicates because this wastes processing capacity.
  • Slides should be bullet points of your narration. Avoid reading directly off your slides.
  • This effect can be reduced by eliminating graphics or shortening the on-screen text.

Spatial Contiguity Principle

  • Printed words and corresponding graphics should be placed close to one another
  • Place arrows from the text to the described portion of picture or graph
  • Avoid having the audience integrate this association independently

Temporal Contiguity Principle

  • An audience has improved learning when the corresponding narration and graphics are presented simultaneously rather than successively
  • It is ideal to sync narration to graphics. You can time the on-screen graphic display such that associated text and graphics appear as you are narrating them

Segmenting Principle

  • Material is best learned when broken into segments, allowing the learner to organize or compartmentalize the presented material
  • Slides should have the material broken into portions with heading slides in between
  • If all slides look similar, it may be difficult for the learner to separate them in their head
  • Instructional videos should be broken into segments for the learner to control the pace or move forward at their discretion

Pre-Training Principle

  • Students learn best then they have previously learned the names and characteristics of the main content
  • Learning in advance allows students to focus on making causal connections of the content rather than focus on the terminology

Modality Principle

  • When multimedia is presented, people learn better when words are spoken rather than printed
  • Speaking the words allows learners to off-load the visual channel onto the verbal channel so the visual channel can focus on the corresponding graphics on screen
  • An exception is when verbal material introduces new technical terms. In that instance, a printed word is just as effective

Personalization Principle

  • Multimedia presentations are retained best when presented in a conversational style rather than a formal style
  • By framing the narration as a conversation, this triggers the learner to be more engaged
  • An example of conversational wording would be stating “your antibodies” rather than more formally, “the antibodies”

Voice Principle

  • Students learn best when listening to a human voice rather than a machine voice
  • This principle applies most directly to video-based multimedia with associated narration

Embodiment Principle

  • Gesturing, eye-contact, and facial expressions by the narrator promote improved learning
  • Human-like action creates a sense of social presence between the instructor and student
  • If the multimedia agent used is a video, any image of a human narrator should include these components

Image Principle

  • Students do not show improved learning when a speaker’s image is presented on a screen (versus not on a screen). An example of this practice would be in a video conference setting where there is a screen with the PowerPoint slides and an additional image of the presenter narrating the lecture. The image of the presenter adds no benefit as only the PowerPoint and the audio narration is necessary.
  • A static image may cause a distraction from the information presented

Optimizing Multimedia Ergonomics and How to Use it In Your Own Presentation

Despite the plethora of PowerPoint guidelines available across the internet, there is actual, tested, empirical evidence of best techniques for retention and learning from multimedia presentations.9 Studies have tested elements of slide design—font, size, text color and text layout—to determine the optimal display of information. This has been tested by looking at speed of reading the slide, recall time, and visual fatigue. Here we will explain optimal multimedia ergonomics and give insight into best techniques for your own didactic presentations.

Font Type

There are two principal font types: serif and sans serif. A serif is a line attached at the end of a stroke in a letter or symbol. Serif style fonts that include these edges include Times New Roman and Georgia. Sans serif fonts do not incorporate this extra stroke and include Arial and Helvetica. Serif font is ideal for PowerPoint as the edges at the bottom of each letter help guide the eye along the line of text.10 Serif fonts have been proven to be more legible and allow for increased reading speed.11

Font Size

The size attributed to text is the angle of perception from the eye. In multimedia, it is important that the font is large enough for everyone to see. Small fonts restrict those seated at a distance from being able to read the content. Additionally, smaller fonts can make it tempting to cram too much information on a slide. The minimum font size that should be used is size 22.12

Text Color Scheme

The scheme refers to the color of the text and how it relates to the color of the background. There are two different types: positive polarity and negative polarity. Positive polarity refers to dark text on a light background, while negative polarity is light text on a dark background. Research has shown that proofreading and word search is improved for positive polarity. Studies also measured physiologic signs of effort (including heart rate, breathing rate, skin conductance, eye strain) and found that these signs are decreased with positive polarity.13 Most importantly, study participants prefer positive polarity. Scientifically, this makes sense as a bright (white) background closes the iris of the eye more thus decreasing the effort of the lens. On the other hand, a dark (black) background does not reflex the iris to close as much and the text may, instead, appear slightly imperfect or fuzzy.13

Text Format

Utilizing a bullet list format is ideal. This allows the presenter to highlight key principles and break the content into a structure easier for a learner’s mind to categorize and recall. Lists should ideally be kept to 3–5 items. When possible, try to keep each bullet point succinct to a single line.14

By combining the multimedia principles and ergonomics listed above, it might just be possible to hold our residents’ attention for an hour and help give them maximum ability to recall information when the time comes for the ABSITE.


  1. Issa N, Mayer RE, Schuller M, Wang E, Shapiro MB, DaRosa DA. Teaching for understanding in medical classrooms using multimedia design principles. Med Educ. 2013 Apr;47(4):388-96.
  2. Berk RA. Research on PowerPoint®: From basic features to multimedia. International Journal of Technology in Teaching and Learning. 2011;7(1):24-35.
  3. Issa N, Schuller M, Santacaterina S, et al. Applying multimedia design principles enhances learning in medical education. Med Educ. 2011 Aug;45(8):818-26.
  4. Earnest WJ. Developing strategies to evaluate the effective use of electronic presentation software in communication education. Dissertation Abstracts International, Section A: Humanities & Social Sciences. 2003;65(3-A),764.
  5. Paivio, A. Imagery and verbal processes. New York: Holt, Rinehart, and Winston; 1971.
  6. Sweller, J. Cognitive load during problem solving: Effects on learning. Cognitive Science. 1988. 12:257-285.
  7. Mayer RE. Multimedia Learning. 1st ed. Cambridge: Cambridge University Press; 2001.
  8. Mayer RE. Applying the science of learning: Evidence-based principles for the design of multimedia instruction. Am Psychol. 2008 Nov;63(8):760-9.
  9. Durso FT, Pop VL, Burnett JS, Stearman EJ. Evidence-based human factors guidelines for PowerPoint presentations. Ergonomics. 2011;19:4-8
  10. Arditi A, Cho J. Serifs and font legibility. Vision Rsch. 2005;45:2926-2933
  11. Gasser M, Boeke J, Haffernan M, Tan R. The influence of font type on information recall. N Am J Psych. 2005;7:181-185
  12. Sanders MS, McCormick EJ. Human Factors in Engineering and Design. 7th Ed. New York: McGraw-Hill Education; 1993.
  13. Buchner A, Baumgartner N. Text-background polarity affects performance irrespective of ambient illumination and colour contrast. Ergonomics. 2007;50:1036-1063.
  14. Cowan N. The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Beh and Brain Sci. 2001;24(1):87-114.

About the Authors

Naomi M. Sell, MD, MHS, is a resident physician in the department of surgery at Massachusetts General Hospital, Boston, MA.

Denise W. Gee, MD, FACS, is an assistant professor of surgery in the department of surgery at Massachusetts General Hospital, Boston, MA.