How to Improve Working Memory: What the Evidence Supports
Practical, evidence-based ways to get more out of working memory: chunking, sleep, exercise and strategy, and what does not work.
Working memory is the mental workspace where you hold and use information for a few seconds: a phone number you are about to dial, the earlier clause of a long sentence, the numbers in a mental sum. It is small, it is easily disrupted, and it matters for reasoning and learning. This article covers what working memory is, what the evidence says can raise your effective use of it, and what is hype.
What working memory is, and how big it is
Baddeley and Hitch (1974) described working memory as a system with a central controller and separate stores for sounds and for visual or spatial information. George Miller's famous 1956 paper put the span at "seven, plus or minus two" items. Later work, notably Nelson Cowan's 2001 review, argued that when you prevent rehearsal and chunking, the true limit is closer to four chunks. The difference matters: the limit is in chunks, not raw items, and a chunk can be as large as you can make it meaningful. You can see this with the digit-span task in our working memory test; typical norms are on the digit span norms page.
1. Make bigger chunks
This is the most reliable way to raise what you can hold. Chess experts remember board positions far better than novices, but only when the positions are meaningful game positions; with randomly placed pieces the advantage nearly disappears (Chase and Simon, 1973). Their working memory is not larger. They have learned to see a handful of familiar patterns instead of twenty separate pieces.
- Group digits into threes or fours: 4-1-5-9-2-6 becomes "415" and "926".
- Attach meaning: dates, patterns, familiar names.
- Learn the structure of whatever you study. Experts chunk automatically because they have a rich mental map.
2. Use external memory on purpose
The most underrated improvement is to stop using working memory for things that can be written down. Notes, checklists, calendars and diagrams free the workspace for thinking. Cognitive scientists call this offloading. It is not cheating; it is the reason writing exists.
3. Reduce interference and overload
Working memory is highly sensitive to distraction. Notifications, background speech and task switching all consume capacity. Practical steps:
- Do one demanding task at a time and close unrelated tabs and chats.
- Take on new information in short bursts with breaks, not in a single long session.
- Reduce the number of things you must keep in mind by simplifying a problem before solving it.
4. Protect sleep
Sleep loss reliably impairs attention and working memory, and reduces how well you consolidate new learning. Cutting sleep to study more tends to backfire. See our article on sleep and cognitive performance.
5. Move regularly
Aerobic exercise is associated with better executive function in many studies, and trials in children and in older adults show modest benefits for attention and memory tasks. Effects are moderate, and exercise is no magic bullet, but it supports sleep, mood and general brain health, all of which affect working memory in daily life.
6. Rehearse and retrieve
Information you retrieve from memory is better remembered later than information you only re-read. This "testing effect" is among the strongest findings in learning research. For working memory in particular, rehearsal and elaboration (explaining something in your own words) turn short-lived information into durable knowledge.
7. Manage stress
Anxiety consumes working memory, because worrying is itself a mental load. Short routines that calm you before a demanding task, such as slow breathing, can make better use of the capacity you have. The claim here is modest: it helps performance under pressure, not the underlying capacity.
What does not reliably work
Practising working memory tasks makes you better at those tasks. Evidence that this improves general reasoning, school grades or everyday memory is weak; meta-analyses found small or no transfer. Dual n-back, for instance, produced excitement after a 2008 study but later reviews did not support broad benefits. Details are in does brain training work?. Supplements marketed for memory also lack strong evidence in healthy adults.
A realistic plan
- Sleep seven to nine hours as a baseline.
- Write things down; reserve your head for thinking.
- When learning, build chunks and explain ideas in your own words.
- Test yourself instead of re-reading.
- Exercise most days.
- Retake our memory test under similar conditions every few weeks if you want to see your own trend. A single score on one day says little.
Sources
- Baddeley, A. D., & Hitch, G. (1974). Working memory. In G. H. Bower (Ed.), The Psychology of Learning and Motivation (Vol. 8, pp. 47–89). Academic Press.
- Miller, G. A. (1956). The magical number seven, plus or minus two. Psychological Review, 63(2), 81–97.
- Cowan, N. (2001). The magical number 4 in short-term memory. Behavioral and Brain Sciences, 24(1), 87–114.
- Chase, W. G., & Simon, H. A. (1973). Perception in chess. Cognitive Psychology, 4(1), 55–81.
- Roediger, H. L., & Karpicke, J. D. (2006). Test-enhanced learning. Psychological Science, 17(3), 249–255.
- Melby-Lervåg, M., Redick, T. S., & Hulme, C. (2016). Working memory training does not improve performance on measures of intelligence or other measures of "far transfer". Perspectives on Psychological Science, 11(4), 512–534.