The Transient Information Effect: Why Great Explanations Don’t Always Stick
In this post, Dr. John Sweller describes how the Transient Information Effect can overload student working memory and what teachers can do about it.
Note: This post is co-authored by Dr. John Sweller, Professor Emeritus at the University of New South Wales
Highlights:
The Transient Information Effect happens when important information disappears before learners can process and remember it.
Dr. John Sweller, who first studied the Transient Information Effect, answers our questions about this overlooked learning challenge.
Turning transient information into something students can revisit (like writing key steps on the board) can help explanations stick.
Consider this scenario: You’ve just walked your class through a tricky problem step-by-step. Heads are nodding, you feel the pacing is just right… and then, two minutes later, students can’t recall the steps you just explained.
It’s not a matter of student inattention or poor explanation. The information simply slipped away before they could process and store it. Even when you account for limited working memory and provide clear, sequential instructions, the learning sometimes still doesn’t stick. So what’s happening here?
The problem is that verbal communication is temporary. Spoken information is fleeting: once said, it vanishes. Students in our scenario didn’t remember the steps a few minutes later because they experienced the Transient Information Effect: when important information disappears before learners can process it and integrate it into long-term memory. The fix is often surprisingly simple: if the content is complex, keep it visible. For example, write key steps on the blackboard and leave them visible until the end of the activity so students can refer back as they work.
The Transient Information Effect is not limited to verbal communication. It occurs whenever information is only visible to a student for a very limited time (e.g., when a teacher speaks, plays a video, displays PowerPoint slides, or presents an animation). It’s a silent killer of learning, because the teacher may be proceeding under the assumption that students recall the presented material, unaware that they are struggling.
To dig deeper into what this means for teaching, and how to counter it, we consulted with Dr. John Sweller. Dr. Sweller is perhaps best known as the researcher who developed Cognitive Load Theory (CLT), but he was also the first to describe, and study, the Transient Information Effect.
Unpacking the Transient Information Effect with Dr. John Sweller
Question: For teachers who haven’t heard of it before, what is transient information?
John: Transient information is any information that is not recorded somewhere so that we can return to it repeatedly. Books or electronic devices such as recorders were invented to turn transient information into permanent information. The invention of writing, drawing, and painting were a part of humanity’s quest to turn transient sensory information into permanent records that could be accessed repeatedly.
Question: What are some of the most common sources of transient information in a classroom?
John: Everything that a teacher says or shows that is not permanently accessible to students is transient. Speaking to a class or showing videos provide examples, as does complex information provided on a PowerPoint that disappear but will be needed to understand subsequent information. Students who take notes in a class are doing so to convert the transient information that they are experiencing into permanent information.
Question: Can you share any studies you have conducted on the Transient Information Effect and how it impacted student learning?
John: There are many studies that compared transient information such as speech to exactly the same information presented in written form, or a video compared to the same information presented as a series of pictures on paper. The Transient Information Effect occurs when a subsequent test indicates that students presented the information in permanent form obtain higher test scores than students presented the information in transient form.
Question: What is happening in working memory when the Transient Information Effect occurs?
John: Working memory can only hold about 7 elements of information simultaneously and process 2-4 of those elements, where processing means combining or dealing with those elements in some way. If students have for example, to simultaneously listen to some information, hold and rapidly process it, working memory may be overwhelmed. In effect, “the system” collapses and the result is that nothing is transferred to long-term memory and so nothing is learned. Transient information can add further stress on this volatile system, making it even harder for learners to process new incoming information.
Question: What are some of the practical steps teachers should be considering to lower the impact of the Transient Information Effect?
John: When dealing with complex information, either do not present it in a transient mode or if it must be presented in a transient mode due to administrative arrangements, ensure that a permanent version is available for students to study later.
Question: Are there situations where transient information isn’t harmful, or might even help learning?
John: Simple information that can be readily held and processed in working memory may benefit by being presented in transient form. Because it can be presented by teachers and processed by students easily and quickly, there is no need to transform it into permanent form and it is likely to be more convenient to leave it in transient form.
Question: If teachers remember just one thing about the transient information effect, what should it be?
John: If students find the information they are dealing with is complex, do not present it in transient form! Presenting it in permanent form will facilitate understanding and learning.
Final Thoughts
We’re deeply grateful to Dr. John Sweller for sharing his time and expertise with us. In our interview, he offered a clear, practical explanation of the Transient Information Effect, and how it plays out in classrooms. His advice is refreshingly straightforward: if it’s complex, put it in a permanent form.
Many experienced teachers already understand the danger of fleeting content, even if they’ve never heard the term “Transient Information Effect.” They know that when material disappears too quickly, students can miss important points, especially if they’re still processing earlier information. For example, when teachers verbally give students a list of instructions, some will struggle to recall them. Writing the instructions on the board or providing a handout is a simple, low-cost fix.
By making the thinking visible and reviewable, teachers give students the time and mental space they need to absorb each step, spot patterns, and connect ideas. This is especially important for beginners when they deal with complex or unfamiliar material.
Practical strategies for reducing the Transient Information Effect:
When preparing your lesson, plan your blackboard or whiteboard use so key information stays visible until the end of the lesson.
Pair spoken explanations with diagrams, timelines, notes, or charts that remain on display during discussion.
Provide written, worked examples of multi-step procedures or problem-solving methods.
Encourage note-taking and explicitly highlight what students should write down.
Use freeze-frames when showing dynamic content, pausing videos or animations to point out key features.
Capture screenshots or stills from videos and include them in notes or slides.
Chunk verbal explanations with quick written recaps, or have a student restate steps aloud while you write them up.
Offer electronic versions of key content, such as videos or microlessons, so students can revisit material at their own pace.
Teachers should also consider how long the information needs to remain visible. For content that’s only relevant to a single lesson, writing on the blackboard or whiteboard works well. But if the goal is to support students across multiple lessons, writing the information on chart paper and posting it in a prominent spot, such as the front of the classroom, keeps it accessible for longer periods. This gives students an easy way to refer back to it while practicing or applying the skill, reducing the need to hold everything in working memory. Creating the chart in front of students has the added benefit of letting them see the thinking unfold step by step, while the pauses that occur as you write naturally slow the discussion and give students extra time to process.
The Transient Information Effect reminds us that how we present content is just as important as what we teach. By reducing unnecessary working memory load, we give students a better chance to understand and retain what they’re learning. Small changes in presentation can yield big gains in comprehension and recall.
Once again, our thanks to Dr. John Sweller for answering our questions.
Nidhi has developed a microlesson on the Transient Information Effect. Try it out!
Readers might be interested in the Japanese art of board work (bansho). Careful board planning allows students to see the structure of the lecture all at once.
https://link.springer.com/article/10.1007/s10857-021-09511-6
As the parent of a kid with ADHD, it would be so incredibly helpful if every teacher thought like this. So often all the info comes verbally and then the class moves on and processes the info by doing some other verbal activity, only it was too transient the first time, and now the activity to use and review the info is transient, too. She often can’t remember a question long enough to process and form a deep answer. Having the information and questions in a more permanent form that she can reference evens the playing field so she can do early college and thrive, rather than being lost and behind.