Working Memory: A Complete Guide to How Your Brain Processes Information, Thinks and Learns

How do you keep everything in mind when solving tough problems? When you read a book, listen to a podcast or have a conversation–how does your brain hold onto all the information?

The answer is something psychologists call working memory.

Unlike long-term memory, which I’ve covered in-depth here, working memory isn’t about remembering the past. Instead, it’s about holding together the present in your mind so you can learn, make decisions and solve problems.

Working memory is essentially your mental bandwidth. If you have a good working memory, or can use yours more effectively, you can think and learn better. Thus, understanding this important facet of your mind is essential for anyone who wants to perform better in work, school and life.

To give you that understanding, I’ve collaborated again with Jakub Jilek, who has his masters in cognitive science and is currently studying for his PhD. We’ve put together a full guide to explaining what your working memory is, how it works, and most of all–how you can apply simple methods to think and learn better.

Side note: Like our last guide, this one is substantial. If you’d like to go over it as a PDF instead of just reading along here (either to print or to save for later) you can join my newsletter and I’ll send you a free copy of the PDF:

Table of Contents

  1. Working Memory
  2. What is Working Memory?
  3. Why Working Memory Matters
    1. How Working Memory Underpins Your Ability to Learn
    1. How can you measure your working memory?
    1. Are all sounds equally harmful to learning?
    2. Does music affect everyone the same way?
    3. How to use sound to boost your learning
    1. Strategies for improving your visuospatial working memory
    2. How to use visualization and drawing to improve learning
    1. The hidden costs of multi-tasking
    2. Who is affected by multi-tasking?
    3. How badly designed textbooks split your attention
    1. How to use chunking as a mnemonic technique
    2. Chunking works by reducing memory load
    3. How experts use chunks
    4. Build chunks with pre-training
    1. Reduce intrinsic load with segmenting and worked-examples
    2. Reduce extrinsic load with visually simple textbooks and a goal-free approach
    3. How to optimize cognitive load
    1. Why does anxiety burden our working memory?
    2. How you can overcome anxiety

    What is Working Memory? The Four Components Underlying Your Ability to Think and Learn

    What is working memory? The easiest way to understand working memory is by visualizing it as a carpenter’s workbench: [1] The carpenter temporarily places tools and materials on the workbench as she builds new products. The workbench has a small size – only a few items can be placed on it at once.

    Similarly, you temporarily store information in your working memory when you’re solving a problem or making a decision. Working memory also has a small capacity – it can only hold a few items at once.

    However, the workbench is not just for keeping materials in one place. It’s a workspace – the carpenter uses it to combine different materials to create new products. Similarly, working memory is not just a simple storage. Working memory enables you to generate new thoughts, change them, combine them, search them, apply different rules and strategies to them, or do anything else that helps you navigate your life.

    By enabling all of these functions, working memory underpins your thinking, planning, learning and decision-making.

    Scientists have developed various models of working memory. In this guide, we will draw on the most popular model, which has been developed by Alan Baddeley. [2] According to this model, working memory can be divided into four components:

    The first component is called the phonological loop. It’s essentially a storage of sounds – it allows you to temporarily memorize digits, words and sentences (by the way they sound).

    The second component is called the visuospatial sketchpad. As the name suggests, the sketchpad stores two- and three-dimensional images of objects.

    The third component is the central executive. Its main responsibility is directing attention and manipulating information.

    Using our workbench analogy, you could think of the the phonological loop and the visuospatial sketchpad as two different vises that hold materials in one position. Each vise can hold a different kind of material (such as wood or metal). Similarly, the phonological loop can hold sounds and the visuospatial sketchpad can hold images.

    You could think of the central executive as the carpenter herself. The carpenter decides which tools and materials to use in the same way as the central executive decides which things to pay attention to. She shapes metal and wood by using chisels, saws and drills to create a new product such as a chair. Similarly, the central executive re-arranges ideas and applies the rules of grammar, logic or algebra to come up with a solution to a problem or make a decision.

    Baddeley’s model also has a fourth component (“episodic buffer”) which we won’t cover here because it’s not so well researched as the other three components.

    You may have also heard of the term “short-term memory”. Scientists currently use this term when they talk about a simple temporary storage (but not manipulation) of information, [3] which can be of any kind (visual or auditory). The term “working memory” is used to talk about the whole storage and manipulation system.

    To give you a quick recap, here’s the three main parts of working memory:

    1. Phonological loop – stores sounds including words, digits, sentences
    2. Visuospatial sketchpad – stores images of objects
    3. Central executive – directs attention and manipulates information

    In this guide we’ll look at all these three components and see how they impact on your learning. In addition, we’ll cover another three important topics, which are closely connected to working memory:

    1. Chunking – the compression of information
    2. Cognitive load – the processing demands placed on working memory
    3. Anxiety – the culprit behind problems with working memory

    One quick thing before we get started. If you’re interested in this stuff, you’ll probably enjoy my weekly newsletter, devoted to the art of learning, productivity and getting more from life. If you sign-up below, I’ll send you a free rapid-learning ebook:

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    Why Working Memory Matters

    Working memory is a key aspect of intelligence. [4] Much of your learning depends on your working memory.

    Think of the last time you followed a hard class. In the beginning, you might have kept up fine. But eventually it became harder and harder to understand what the professor was saying. Even though you tried your best to pay attention, you left feeling confused and frustrated.

    It turns out that the culprit is likely an overloaded working memory [5] (read Summary and Conclusion for other possibilities). The study material required your working memory to process too much new information at the same time. As a result, the system became overwhelmed and broke down.

    Even if you don’t regularly attend confusing lectures, understanding how your working memory functions is essential for learning better.

    How Working Memory Underpins Your Ability to Learn

    In order to learn, you first must comprehend. [6] [7] To do this, your working memory is always involved:

    Your phonological loop must keep track of the sounds of the words you read or hear. Your central executive must constantly update these sequences as you go along. Finally, these meanings need to be integrated so you can understand everything. If any of these processes fail, you’ll get lost and confused.

    Solving problems is also essential to learning. [8] Once again, your working memory is working hard.

    Consider trying to solve the problem of adding two numbers:

    Most of us learn how to add numbers like these in grade school (the solution is 152). Despite the simplicity, however, there’s a lot of complicated cognition to pull off this calculation. [9] [10]

    Your visuospatial sketchpad first has to store a visual representation of the symbols. Your central executive has to apply the rules of addition and store the intermediate steps (e.g. 80 + 60). Finally, your phonological loop has to maintain the subvocal instructions to control the operation (“add eighty and sixty” etc.). [11] If any of these problems fail the result is, again, confusion and getting lost.

    Besides comprehension and problem-solving, working memory underpins many other learning skills. Note-taking [12] requires you to quickly store and process what is has just been said while simultaneously processing what is being said right now.

    It shouldn’t surprise you now that working memory capacity has been found to be significantly connected to reading comprehension [13][14] , maths [15] and problem-solving. [16] Students who have a better working memory enjoy better grades. [17] Most importantly, higher working memory capacity predicts better learning outcomes and achievement. [18][19][20]

    Can You Improve Your Working Memory

    You’ve probably heard of memory experts who can remember astonishingly long sequences of random digits or words. For example, Rajan Mahadevan is able to correctly retrieve a staggering 31,811 digits of the mathematical constant pi (long-term memory). He can also remember up to 63 randomly presented digits or words (working memory). [21] Another mnemonist, Suresh Kumar Sharma, holds the Guinness world record for managing to recite pi to 70,030 digits without making any mistakes. [22]

    You may be thinking that it’s impossible to achieve such amazing feats unless you’re born naturally gifted.

    Although both of these mnemonists have likely had an above-average working memory since childhood, genetic predispositions are by no means the whole story. If these champions were naturally blessed with a fantastic working memory, then we would expect them to excel in all tasks requiring working memory, right?

    Researchers decided to test this idea. [23] Instead of digits or words, they gave Rajan Mahadevan series of symbols (such as !, @, *, +, etc.). Can you guess how many symbols Rajan managed to remember?

    To everyone’s surprise, Rajan could only keep 6 of these symbols in his working memory – the same as an average university student.

    When interviewing these and other mnemonists, scientists found that they had devoted extensive time of practice to hone their memory. What’s more important, they use highly sophisticated and refined versions of mnemonic techniques such as the method of loci or the story method. [24]

    All these results suggest that working memory is (to some degree) a skill like any other – if you practice it, you can improve it.

    While the jury is still out whether and to what degree it’s possible to improve the core processes of working memory, [25] scientists have discovered many techniques that help you make your working memory more efficient and effective. In the following sections we’ll describe how you can apply these techniques to boost your comprehension and problem-solving skills.

    How can you measure your working memory?

    If you set out to improve your working memory, it can be useful to know how you can measure it. Scientists distinguish between short-term memory capacity and working memory capacity. [26]

    Short-term capacity is simply your ability to temporarily store of small amounts of information. [27] This information can be digits, letters, words, symbols, pictures, scenes, or anything else. Short-term memory span is the number of items that one can store in their short-term memory.

    Would you like to know your digit span? Try this online test. Scroll down the webpage, uncheck “sound enabled”, set the starting sequence length to 3 and click start. Do this at least three times and then compute the average, which will be your digit span. You can also click “repeat” if you want to repeat a sequence with the same number of digits.

    The average human span is 4 items, [28] although the exact number depends on the type of items. People can typically remember more letters than words and more digits than letters. The average digit span is 7 digits.

    Working memory capacity is your combined ability to store and manipulate information. It’s traditionally measured with complex span tasks (such as the operation span) and the famous n-back. These tests can’t be taken online, but you can download them here.

    Phonological Loop: How Music Disrupts Your Studies

    Phonological loop is the first kind of short-term memory storage which stores sounds. Being able to have a conversation, listen to music and understand a lecture all depend on your phonological loop.

    As you read these lines, your phonological loop is working at every moment. It uses subvocalisation (your internal voice) to translate visual information (digits, letters, words and sentences) into auditory information, which is then processed to extract meaning. [29]

    If the subvocalisation process is disrupted, it will be hard to maintain information in your phonological loop. As a consequence, your comprehension will suffer. To see this on yourself, try the following experiment:

    If you haven’t already done so, measure your digit span. After you’ve done that, measure your digit span again. This time, however, firstly start playing a favorite song of yours that contains lyrics (it shouldn’t be a purely instrumental piece). Set the volume to a comfortable level (not too quiet but not too loud). What is your digit span now?

    It’s likely that your digit span is now one or more digits lower. [30] This is because the music interfered with the subvocalisation process, which was thus less effective at encoding information in your phonological loop.

    Are all sounds equally harmful to learning?

    Many studies have shown that listening to many kinds of sounds and music can have a profoundly negative impact on your working memory, reading comprehension and mathematical problem-solving. [31] For instance, one study has shown that students who revise in a quiet environment later perform 60% better in an SAT comprehension test than their peers who listen to music (with lyrics). [32]

    However, different kinds of sounds have different effects. Firstly, the detrimental effect is much stronger with vocal music compared to instrumental music. One study showed that students who revised without music were 10% better than students who revised while listening to instrumental music. [33]

    Secondly, it doesn’t matter if you don’t understand the language. Foreign language also impairs working memory. [34] Thirdly, although even pure tones can disrupt performance, the tones have to fluctuate. If the pure tone has a constant pitch, it doesn’t have a harmful effect on memory. [35]

    Does music affect everyone the same way?

    Listening to music doesn’t affect everyone in the same way. In general, individuals with a high working memory capacity are more resistant to the harmful effects of music. [36]

    However, students are very bad at predicting what effect music has on their performance. Interestingly enough, the students who prefer listening to music while studying are also those whose reading comprehension is most likely to suffer due to interference from music. [37]

    Why do so many students listen to music although it impairs their learning? Why do they even feel that they benefit from this? We believe that the reason for this might be twofold:

    Firstly, music could help reduce anxiety and help one calm down, which may be beneficial for studying. [38] Secondly, music could drown out even more disrupting external noise, which might actually help to protect working memory.

    Interestingly, although white noise seems to worsen the performance of students with normal attention, it can actually improve the performance of students with attention problems. [39]

    In general, we would recommend that you avoid listening to music while studying (especially vocal music). It’s important that you study in a quiet environment where no-body is speaking or making any other noise. The exception to this rule is when you’re preparing for an exam that will take place in a noisy environment. In this case, it’s beneficial to spend some time revising in a noisy environment (to see why, check our Complete Guide on Memory, section “Context-dependence” ).

    If you cannot revise in a quiet environment, the best way to reduce noise is by using earplugs. Alternatively, a not too harmful option is to listen to white noise (check out the plethora of white-noise nature sounds on YouTube). If you do have to listen to music, go for instrumental music.

    How to use sound to boost your learning

    The first strategy to improve your learning is by protecting your phonological loop from interfering sounds. Scientists have found yet another strategy that significantly boosts learning and that also makes use of sound.

    In an intriguing study, students had to memorize lists of words. [40] The first group read the words aloud, the second listened to a recording of their own voice reading the words, the third group listened to someone else, while the fourth group studied the words in silence. Interestingly, the first group showed the best performance (20% better than the fourth group), followed by the second, third and fourth group.

    The advantage of reading aloud over reading silently for subsequent memory performance is called the “production effect”. [41]

    Scientists believe that producing words makes them more distinctive than reading them silently because you additionally use your vocal cords and facial muscles. [42]

    To harness the production effect, however, you shouldn’t read aloud all of your study material. Distinctiveness is relative – a word read aloud will stand out in the context of silently-read words but it won’t stand out if all other words are also read aloud. [43] Therefore, to get the most benefit, we recommend that you use the production effect only for a selection of the most important information.

    In summary, we recommend the following: