Why Mayer's redundancy principle tells us to explain visuals with either audio or text—not both

Let’s talk about a quiet hero in learning design: Mayer’s Multimedia Theory. If you’ve ever built or evaluated a training module, you’ve probably run into a simple tension—how much is too much when you show visuals and tell the story at the same time? That tension is at the heart of the Redundancy Principle, one of Mayer’s key ideas. It’s not flashy, but it’s incredibly practical. And yes, it matters a lot for CPTD-style learning experiences—where clear, efficient communication can make or break a learner’s progress.

What the Redundancy Principle really says (in plain language)

Here’s the thing: when you present visuals and say the same thing on audio or text at the same moment, you can actually slow people down. Our brains have to juggle two channels that are telling the same story. That duplication can fragment attention and bump up cognitive load. The result? Learners might miss the essential point, or feel fatigued halfway through.

Think of it like watching a screen where a chart is labeled with every axis name, and a narrator repeats those labels out loud at the same speed. The chart is doing the heavy lifting, but the narration adds a constant echo of repetition. Your brain starts filtering, not learning. The principle isn’t saying “never use both channels.” It’s saying: use one clear channel to explain visuals, and reserve the other for information that genuinely adds something new.

Why this matters for talent development work

In the world of talent development, we’re often juggling microlearning videos, job aids, and slide decks. The CPTD framework—covering areas like instructional design, learning experience, and performance improvement—asks us to craft materials that are not only accurate but also easy to digest. When we apply the Redundancy Principle, we’re helping learners stay in the flow. They can focus on what matters—the concept, the relationship, the application—without fighting through duplicate wording.

Here’s a relatable example: you publish a short explainer video about a new performance metric. If the video shows a chart and the narration simply repeats the labels and numbers you already see on-screen, you add little value. Instead, you can either:

• Use concise captions that highlight the key takeaways while the visuals do the explanation, or

• Use a narration that expands on the image with context, while the on-screen labels are minimal or even omitted.

The sweet spot is where the visual, the spoken word, or the written text each contribute something unique. That’s where real learning happens.

A practical guide to applying the Redundancy Principle

If you’re designing something for CPTD-aligned learning, here are bite-size tips you can start using today:

• Decide what each channel will do. For visuals-heavy slides, let the visuals tell the story and use audio sparingly to add nuance or real-world examples. If you opt for text captions, keep them short and focused on support, not repetition.

• Cut the double-babble. If your slide already shows a diagram with labels, remove the spoken repetition of those same terms. Conversely, if your narration explains a process that isn’t obvious from the image, you’re okay to use audio to fill that gap.

• Leverage accessibility thoughtfully. Redundancy isn’t the friend here, but accessibility is. If a learner can’t hear well, alternative text or captions become a lifeline. The rule is adapted to help everyone, not to complicate things.

• Use signaling to guide attention. Instead of repeating, guide learners’ eyes and ears to the essentials. Bold a key idea on the slide, add a short highlight in the narration, and let the visuals do the rest.

• Build with storyboards. Map out a sequence where each element has a clear purpose. If you place text on a screen, pair it with visuals that illustrate the concept in a fresh way—no echoing of the same words.

• Test with real users. Quick, informal usability checks can reveal where redundancy sneaks in. If a colleague says, “I didn’t learn anything new here,” that’s your cue to rework the balance.

• Consider the context and audience. In a noisy environment or when learners are multitasking, audio might be harder to process. In such cases, rely on clean visuals with minimal narration, or vice versa.

A few practical design patterns that fit CPTD principles

• Diagram plus narration with nuance: Show a workflow diagram and use audio to describe decisions or exceptions that aren’t obvious from the diagram alone.

• Diagram with concise captions: A chart or map appears with a few carefully chosen captions that summarize the takeaway; the narration remains off or very restrained.

• Text-forward with visuals as anchors: Short, crisp text points paired with relevant visuals that strengthen the concept without repeating the text in the audio.

Where this fits into the bigger CPTD picture

The CPTD domains emphasize not just knowledge, but how people learn and perform. The Redundancy Principle ties directly into instructional design decisions, content strategy, and learning experience design. It nudges designers toward lean, purposeful content—streamlined messages, sharper visuals, and a delivery mode that respects cognitive load.

If you’re building modules for leadership development, onboarding, or performance improvement initiatives, a mindful application of this principle can make a real difference. Imagine a microlearning series on coaching conversations. You could:

• Use short narration to model the conversation flow, while the visuals show a sample dialogue in action.

• Or present a scenario with text-based prompts and a voiceover that adds reflective questions, avoiding repetition of the dialogue itself.

The goal is frictionless learning—where the method of delivery serves the learner, not the creator’s preference. When content feels clear and purposeful, retention tends to follow, and that’s exactly what modern talent development aims for.

A quick, memorable mental model

Think of your content like a well-tuned orchestra. The visuals are the instruments, the narration is the conductor, and the text is the score. The Redundancy Principle invites you to decide which instrument carries which part of the melody at any given moment. When everyone plays to their strengths, the music (aka learning) lands smoothly.

Common pitfalls to avoid (so you don’t trip on your own notes)

• Don’t narrate every label on a chart. If you must describe something, add a detail that isn’t visually explicit—otherwise it’s just duplicating what learners already see.

• Don’t rely on dense text to replace visuals. A chart without explanation can be hard to interpret; the goal is synergy, not repetition.

• Don’t assume more channels equal deeper learning. More channels can mean more noise if they repeat the same message. Clarity beats volume.

A few tools and ways to test ideas

If you’re prototyping, tools like Articulate Storyline, Captivate, or Camtasia make it easy to toggle narration on and off, add captions, or create clean visuals. Run a quick A/B check with a friend or a colleague: one version uses narration with minimal text, the other uses text captions with the visuals. Which one helps you recall the main idea faster? The answer isn’t a mystery once you listen for cognitive load.

Beyond the classroom: everyday learning moments

The Redundancy Principle isn’t just for formal training. It shows up in onboarding emails, quick guides, or internal e-learning that busy professionals rely on. The moment you notice overlapping channels doing the same job, you have a chance to reframe. That tiny adjustment—choosing one clear channel for explanation—can ripple outward, making it easier for teams to absorb and apply new concepts.

A final thought to carry forward

Design is a conversation between ideas and how they’re presented. Mayer’s Redundancy Principle is a reminder to be merciful with learners’ attention. When visuals and narration—or visuals and text—don’t overlap, learners gain space to think, connect, and apply what they’ve learned. That’s the essence of effective talent development: content that respects the learner’s bandwidth and still delivers a compelling, memorable experience.

If you’re curious to explore this a bit more, try a small project: pick a topic you’re passionate about, sketch a quick diagram, and craft two versions—one with narration that explains the diagram, and one with captions that do the same. Compare how you feel after viewing each. You might be surprised by how a single design choice can shift the whole learning moment. And that, in the end, is what good design is all about: clarity, relevance, and a touch of human insight.