The science of revision

Illustrations and words

Research has shown that revising with words and pictures doubles the quality of responses by students.1 This is known as ‘dual-coding’ because it provides two ways of fetching the information from our brain. The improvement in responses is particularly apparent in students when asked to apply their knowledge to different problems. Recall, application and judgement are all specifically and carefully assessed in public examination questions.

Retrieval of information

Retrieval practice encourages students to come up with answers to questions.2 The closer the question is to one you might see in a real examination, the better. Also, the closer the environment in which a student revises is to the ‘examination environment’, the better. Students who had a test 2–7 days away did 30% better using retrieval practice than students who simply read, or repeatedly reread material. Students who were expected to teach the content to someone else after their revision period did better still.3 What was found to be most interesting in other studies is that students using retrieval methods and testing for revision were also more resilient to the introduction of stress.4

Ebbinghaus’ forgetting curve and spaced learning

Ebbinghaus’ 140-year-old study examined the rate in which we forget things over time. The findings still holds true. However, the act of forgetting things and relearning them is what cements things into the brain.5 Spacing out revision is more effective than cramming – we know that, but students should also know that the space between revisiting material should vary depending on how far away the examination is. A cyclical approach is required. An examination 12 months away necessitates revisiting covered material about once a month. A test in 30 days should have topics revisited every 3 days – intervals of roughly a tenth of the time available.6


Students: the more tests and past questions you do, in an environment as close to examination conditions as possible, the better you are likely to perform on the day. If you prefer to listen to music while you revise, tunes without lyrics will be far less detrimental to your memory and retention. Silence is most effective.5 If you choose to study with friends, choose carefully – effort is contagious.7


1. Mayer, R. E., & Anderson, R. B. (1991). Animations need narrations: An experimental test of dual-coding hypothesis. Journal of Education Psychology, (83)4, 484-490.
2. Roediger III, H. L., & Karpicke, J.D. (2006). Test-enhanced learning: Taking memory tests improves long-term retention. Psychological Science, 17(3), 249-255.
3. Nestojko, J., Bui, D., Kornell, N. & Bjork, E. (2014). Expecting to teach enhances learning and organisation of knowledge in free recall of text passages. Memory and Cognition, 42(7), 1038-1048.
4. Smith, A. M., Floerke, V. A., & Thomas, A. K. (2016) Retrieval practice protects memory against acute stress. Science, 354(6315), 1046-1048.
5. Perham, N., & Currie, H. (2014). Does listening to preferred music improve comprehension performance? Applied Cognitive Psychology, 28(2), 279-284.
6. Cepeda, N. J., Vul, E., Rohrer, D., Wixted, J. T. & Pashler, H. (2008). Spacing effects in learning a temporal ridgeline of optimal retention. Psychological Science, 19(11), 1095-1102.
7. Busch, B. & Watson, E. (2019), The Science of Learning, 1st ed. Routledge.

Levels of learning

Based on the degree to which you are able to truly understand a new topic, we recommend that you work in stages. Start by reading a short explanation of something, then try and recall what you’ve just read. This has limited effect if you stop there but it aids the next stage. Question everything. Write down your own summary and then complete and mark a related exam-style question. Cover up the answers if necessary, but learn from them once you’ve seen them. Lastly, teach someone else. Explain the topic in a way that they can understand. Have a go at the different practice questions – they offer an insight into how and where marks are awarded.