Creating Accessible Video Content for Single- and Dual-Channel Learners

If you’re adding any kind of video in your learning content, you must think about accessibility needs for learners who will access your media in different ways. Multimedia accessibility differs based on whether the learners are single-channel or dual-channel learners. Dual-channel learners access videos with both their visual and auditory senses. That is, they watch and hear the video at the same time. Single-channel learners, on the other hand, access multimedia through one sensory channel—this could be either visual or auditory channels, but not both.

There are several research-supported principles for designing multimedia that can make learning more effective by reducing cognitive load for both types of learners [1].

Video content is most effective and accessible when it is divided into short segments. While there is no ideal length, 8-10 minutes is generally recommended. Shorter videos of 4-5 minutes are advised for most learners while longer videos up to 20 minutes may work well for adult learners depending on the content and presentation.

If longer videos are needed to convey content, you may want to integrate breakpoints in the video at key points. Interactive technologies, along with learning prompts or questions, give the learner a chance to reflect, brainstorm and check their understanding of the content, leading to greater engagement and retention.

When making educational video content, create an outline or storyboard before scripting and recording your video. This type of planning is critical for all types of video production, from live-shoots, self-records to animated or motion graphics videos. Your script will prepare you for the live recording and will ensure that the recording progress goes smoothly and that you get across all of your teaching messages and points.

You may want to integrate on-screen text or other visuals into your video to emphasize certain messages. Any on-screen text or visuals should be kept to a minimum and serve as clear and simple reinforcement that adds value to your message and helps build your story. For example, key words can be emphasized by positioning them with relevant, value-added visuals. This helps the brain process the image and text together, leading to greater resonance and retention. Conversely, if the visuals are complex, try using basic animation features to provide attentional cues for the learners—highlights, circles or arrows are examples of such cues.

The quality of the instructor’s voice is key to developing engaging content. It should be clear, pleasant and conversational in tone. When reading the script, the best practice is to imagine that you are having a conversation with a person, not the camera. Videos should not sound like a formal essay. So, when you read your script aloud, speak like you would in a classroom, with clarity, enthusiasm and pausing between thoughts. Practicing the script multiple times before recording is key to expressing the material naturally and to ensuring a smooth and efficient recording session.

Creating accessible videos for single-channel auditory learners

For those who access video content primarily through audio, the clarity and precision of narration is crucial for accessibility. For example, if you are teaching about addition, don’t say “So as you can see, when we add these two numbers, we get a sum of 14”. A person who accesses through only auditory channels will be left confused about what the two add-ons are. Therefore, before recording the video, read through the script to identify and modify any ambiguous language that requires the visual for understanding.

Creating accessible videos for single-channel visual learners

For learners who access video primarily through visual channels, the addition of closed captioning will make content more accessible. This differs from simply putting the script directly on the slides. Always having the captions posted is called open captions, and for dual-channel learners, this can actually be a barrier to learning since it increases cognitive load to see both the visuals and text on the screen. This is why we recommend using closed captioning which can be turned on and off.

Another option is to provide visual learners with a separate copy of the video transcript. However, this should a secondary option it is less accessible than closed captioning—when using a transcript, visual learners will need to switch between the video and the document thereby losing the benefit of seeing the images and narration together.

Mayer’s “Cognitive Theory of Multimedia Learning” [2] provides a good overview for understanding alternate content presentation formats for different learners. As designers of eLearning materials, it is important to ensure that multimedia content works for the intended learner. Following these basic tips can help you create video content for teaching that is accessible to different types of learners and as many learners as possible.

References

[1] Mutlu-Bayraktar, Duygu, Veysel Cosgun, and Tugba Altan. “Cognitive load in multimedia learning environments: A systematic review.” Computers & Education 141 (2019): 103618.

[2] Mayer, Richard E. “Cognitive theory of multimedia learning.” The Cambridge handbook of multimedia learning 41 (2005): 31-48.