Imagine your brain as a web browser. You’ve got a dozen tabs open: Google docs, a video lecture, Spotify, maybe three spreadsheets. Everything’s running fine until… whirrrr. Your laptop fan screams, the cursor freezes, and your brain’s equivalent of “spinning beachball of death” kicks in.

That’s Cognitive Load Theory (CLT) in action.

Cognitive Load Theory, first proposed by Australian educational psychologist John Sweller in the late 1980s, explains how our working memory, the brain’s short-term, “active” memory system, has a limited capacity for processing information. Simply put, when we overload our brains, learning slows down or even stops altogether.

At its heart, CLT is the science of how much your brain can handle at once while trying to learn something new. And in the immortal words of Goldilocks:

  • Too little load = boredom.
  • Too much load = burnout.
  • Just the right load = deep, efficient learning.

(Goldilocks did say that, right?)

Anyway, in this article, I’m going to tell you everything you could possibly need to know about Cognitive Load Theory, including why you should care about it as a learner, an educator, or a parent.

Where Did Cognitive Load Theory Come From?

That educational psychologist I mentioned, Sweller, was fascinated by why some students learned more effectively than others, even when studying the exact same material. He found that the way information is presented plays a massive role in how well we can absorb it.

His early experiments (Sweller, 1988; Sweller et al., 1998, Educational Psychology Review) revealed that learners performed better when instructional materials were designed to reduce unnecessary mental effort, thereby freeing up brainpower to focus on understanding instead of simply surviving the lesson.

This discovery helped launch an entire field of instructional design built around managing cognitive load.

I mean, it makes sense, right? 

Have you ever tried cramming a semester’s worth of studying into the night before a test? It didn’t work, did it? That’s because your working memory cannot instantly download endless information like a computer.

Computer busy loading

How Does Working Memory Actually Work?

To understand Cognitive Load Theory, it helps to know how your brain processes information.

Your sensory memory takes in everything around you: sights, sounds, words, etc. Then, your working memory (sometimes called short-term memory) grabs the bits that seem relevant, holding them temporarily while you make sense of them.

If you practice, connect, or rehearse the information enough, it’s encoded into your long-term memory, where it becomes knowledge you can actually use. 

But here’s the catch…

Working memory can only hold about 4 ± 1 chunks of information at a time (Cowan, 2010, Behavioral and Brain Sciences). Anything beyond that? It spills over, gets lost, or distracts from comprehension.

That’s why cramming never works.

Side note: The evolutionary story behind all of this is elegantly simple: your brain’s priority is to keep you alive, which means minimizing the amount of energy it spends on remembering irrelevant information. And while you might think that remembering chapter 4 of your biology textbook is important, your brain sure won’t if it’s only ever passively reviewed it once. 

However, if you repeatedly reviewed that chapter and answered questions on it, by practicing biology flashcards, for example, it would convince your brain to hold onto that information. Why? Because (1) you keep seeing it again and again and (2) you’re prompting your brain to actually use that information to answer questions.

Jeff Goldblum mind blown

Now, let’s get super nerdy…

What Are the Three Types of Cognitive Load?

Sweller broke down mental effort into three categories: intrinsic load, extraneous load, and germane load. Why should you care about any of this? Because understanding them is key to optimizing how you study or teach.

1. Intrinsic Load: the Inherent Difficulty of the Material.

Let’s say you’re in high school…

Basic addition? Easy.Quantum mechanics? Your neurons might protest.

Intrinsic load can’t be eliminated, only managed, by breaking complex tasks into smaller, digestible chunks. (This is one of the reasons I love digital flashcards as an efficient way to learn content-heavy subjects.)

2. Extraneous Load: the Bad Kind.

We all have that one friend who is a terrible storyteller. We love them, but WOW can they ruin a perfectly good story with totally irrelevant details and distracting side stories. The same happens in learning. Extraneous load is the mental clutter caused by poor instructional design: confusing explanations, irrelevant details, chaotic visuals, or a teacher talking in circles.

Extraneous load doesn’t help learning, it actively blocks it. (Just like that friend blocks people from wanting to listen to their stories.)

3. Germane Load: the Good Kind.

This is the mental effort that actually contributes to building new schemas. (Schemas are organized networks of understanding.) When you reflect, connect concepts, or practice retrieving content from memory (by answering questions), you’re increasing germane load and strengthening your learning. 

The goal of great teaching (and studying) is to minimize extraneous load and maximize germane load, all while keeping intrinsic load at a manageable level.

Side note: Some later literature (post-2010) has proposed that “germane load” is not a separate type but rather a subcomponent of intrinsic load devoted to learning-relevant processing (Kalyuga, 2011; Sweller, 2010). But the point remains the same.

Why Does Cognitive Load Matter for Learners (and Teachers)?

Time to get schooled

Okay, so why should you care about all of this?

Because no matter how motivated or intelligent you are, your working memory has hard limits. When cognitive load exceeds those limits, the results are familiar:

  • You reread the same paragraph three times
  • You blank on a test question you know you studied
  • You lose focus halfway through a lecture

For teachers, CLT highlights the importance of presentation and pacing. Overloading students with dense PowerPoints or multitasking lessons doesn’t just confuse them, it neurologically prevents them from learning effectively.

For students, it’s a reminder to structure your study sessions intelligently:

  • Don’t marathon-read entire chapters in one sitting
  • Don’t juggle five topics at once
  • Don’t rely on passive review (like rereading or highlighting)

Instead, study in focused, bite-sized sessions, give your brain time to process, and use active recall to strengthen understanding, all of which reduce unnecessary load.

Zone of Proximal Development: The Learning “Sweet Spot”

Cognitive Load Theory isn’t the only framework that tries to pinpoint the “sweet spot” for learning. Decades before John Sweller, Russian psychologist Lev Vygotsky proposed a remarkably similar idea called the Zone of Proximal Development (ZPD), the space between what a learner can do independently and what they can do with guidance or support.

Vygotsky argued that meaningful learning happens within this zone: when a learner is challenged just enough to stretch their abilities but not so much that they become frustrated or lost (Vygotsky, 1978; Chaiklin, 2003). 

In many ways, the ZPD maps neatly onto Cognitive Load Theory’s “optimal load” concept.

  • If the material is too easy, cognitive load is low and the learner is bored: outside the ZPD.
  • If the material is too difficult, cognitive load overwhelms working memory: also outside the ZPD.
  • True learning happens in the middle, where intrinsic load is balanced with the right amount of support, allowing learners to gradually internalize new skills and concepts: a teaching strategy called “scaffolding”.

Teachers often operate inside this zone intuitively: by scaffolding lessons, modeling tasks, and giving feedback that fades as competence grows. And learners can apply the same principle when studying solo: focus on material that’s just beyond comfort level but still within reach with effort and review.

The question now is…

How Can You Manage Cognitive Load While Studying?

Here are some practical, science-backed tips to keep your working memory in top gear:

1. Break It Down

Chunk large topics into smaller, concept-based units. I’ve said it before and I’ll say it again. Flashcards are an excellent medium for this. But save a tree and use a digital flashcard app. Opt for one that uses spaced repetition, like Brainscape. Those offer the most efficient study experience.

Defeat the forgetting curve with spaced repetition
The brain naturally forgets information over time. But by repeating your exposure to that information at precisely-timed intervals—a concept called “spaced repetition”—you can defeat the forgetting curve and retain knowledge far more efficiently than cramming.

2. Limit Multitasking

Every extra stimulus (think: browser tabs, email notifications, text messages from a whiny Tinder date) eats into your working memory. The solution is simple: close any unnecessary application, tab, and distraction. Focus on one task at a time. 

3. Space Out Your Learning

Don’t cram. It. Never. Works. Spacing out your reviews over days or weeks reduces overload and strengthens memory consolidation (Cepeda et al., 2006, Psychological Science).

4. Use Retrieval Practice

Actively recalling information (rather than re-reading it) increases germane load and builds stronger memory networks. This could look like answering questions on the content you’re trying to learn, thereby actively diving into your brain’s memory banks to retrieve (or recall) that information from scratch. (Again, this is something that is inherently built into how digital flashcard apps work.)

5. Simplify Materials

If a resource looks confusing or overwhelming, simplify it. Get yourself back into that Zone of Proximal Development, remember? Rewrite, rephrase, or summarize it in your own words or by making flashcards for it. The less mental “noise,” the more efficient your learning becomes.

Side note: Recent research shows that adaptive scaffolding (support that dynamically adjusts to a learner’s performance) can help reduce extraneous cognitive load and improve learning outcomes in simulation-based tasks. For example, Faber et al. (2024) conducted a randomized study in medical education and found that tailored scaffolding improved speed and decreased cognitive load among learners.

What Happens When Cognitive Load Is Too High?

When your working memory is overwhelmed, your brain goes into cognitive triage:

  • It drops information before encoding it
  • It skips connections between concepts
  • It struggles to transfer learning into long-term memory

In other words, you’re working hard… but not learning efficiently.

Symptoms of cognitive overload include:

  • Fatigue or frustration while studying
  • Forgetting recently learned information
  • Confusion about how concepts fit together
  • “Blanking out” under stress
  • Poor test scores
  • Graduating from High School when you’re 26

Sound familiar? That’s not lack of intelligence: it’s simply poor load management. (Although one might question one’s intelligence if one KEEPS cramming for tests, even after repeatedly getting the same bad results.)

How Do Flashcards Leverage Cognitive Load Theory?

If you couldn’t tell, I’m a huge fan of flashcards. And that’s because they help your brain stay in that sweet Goldilocks zone between “too easy” and “too much”. They:

1. Deliver One Concept per Flashcard

You can create each card to focus on a single idea, thereby minimizing intrinsic load. You process one fact, one definition, or one concept at a time. 

Oh, and by the way, a single "concept" (or learning objective) could be as long as several paragraphs or bullet points. For example, if you were to explain all of the environmental factors that influence the terroir of Burgundy, France, you might talk about the influence of mountains, bodies of water, soil type, rainfall, and winds. 

Flashcards can get really granular but they can also test you on a concept or idea that knits together a greater breadth of knowledge. As long as that learning objective is discrete in its scope (Burgundian terroir) it should make for an effective flashcard.

2. Automate Spaced Repetition

You can repeat flashcards based on how well you knew them: more often if you didn’t know a concept and less often if you did. You can do this manually by sorting your flashcards into an “easy” pile, which you only review again after a while, and a “hard” pile, which you review again immediately. 

However, like I said, I prefer digital flashcard apps that have much more sophisticated spaced repetition delivery systems and allow you to carry around as many flashcards as you need to crush every exam between here and grad school on your phone.

3. Facilitate Confidence-Based Learning

Brainscape flashcard with numbered buttons that allow people to rate how well they knew the answer
Some flashcard apps, like Brainscape, prompt you to rate how well you knew the answer on a scale of 1 (not at all) to 5 (totally). This informs the app's spaced repetition algorithm how frequently to show you that card again.

The other cool thing about digital flashcard apps is that they facilitate confidence-based repetition. By rating your confidence after studying each card (like you see in the image above), you’re actively metacognitively engaging: you’re thinking about your thinking. In simpler terms, you’re asking yourself: “how well did I know this?” And doing that after reviewing each flashcard helps that information sink in just a little bit deeper.

4. Are Visually Simple, Minimizing Chaos

Finally, the minimalist appearance of a single flashcard avoids the distractions and chaos that increase extraneous load. You focus purely on that single concept: one at a time.

(Just remember that flashcards are a powerful supplemental tool for learning any content-heavy subject, but they cannot replace your main learning/lesson materials that explain a subject in greater detail and context.)

So, What’s the Takeaway?

Cognitive Load Theory reminds us that more isn’t always better when it comes to learning.The goal isn’t to stuff your brain with more information, it’s to optimize how that information is processed.

When you…

  • Simplify your study materials,
  • Learn in small, spaced chunks over longer periods of time, and
  • Actively engage with content,

… you’re aligning your brain’s architecture with how memory actually works.

Brainscape doesn’t just espouse this principle, it embodies it. Every flashcard, every review, and every progress rating is designed to help you learn more efficiently, without frying your mental circuits.

Additional Reading (if you’re a sucker for punishment)

If you loved this, you’ll also love these other nerdy science articles we wrote about:

References