Why spaced repetition makes verbatim memorising stick
The night before an English assessment, most of us do the same thing: read the quotes over and over until they feel familiar, then hope the feeling lasts until the exam. Sometimes it does. A week later, almost none of it is left.
That fade has been measured for a long time. In 1885, Hermann Ebbinghaus taught himself lists of nonsense syllables and tracked how quickly they disappeared. Forgetting was steep in the first hours and days, then levelled off. When researchers at the University of Amsterdam repeated the experiment in 2015 with modern controls, they found the same curve (Murre and Dros, 2015). Memory leaks fastest right after you fill it, which is exactly why the night-before cram feels fine on the day and empty a week later.
The problem with re-reading
Re-reading feels productive because the text gets more familiar with every pass. But familiarity is recognition, and an exam or a stage demands recall: producing the words with nothing in front of you. They are different skills, and training one does not do much for the other.
In a 2006 experiment, Henry Roediger and Jeffrey Karpicke had students learn short prose passages. Some read a passage four times. Others read it once, then spent the same time practising recalling it. A week later, the re-readers could reproduce about 40 per cent of the passage, while the recall group managed about 60 per cent (Roediger and Karpicke, 2006). A follow-up in Science found the same pattern with foreign-language vocabulary: once you can recall a word, extra re-study adds almost nothing, while extra recall practice keeps paying off (Karpicke and Roediger, 2008).
Psychologists call this the testing effect. Robert Bjork's broader term is "desirable difficulties": practice that feels harder, like dragging a line out of memory instead of reading it again, is the practice that lasts (Bjork, 1994).
Timing matters as much as method
The other half of the picture is when you practise. A meta-analysis covering decades of experiments found that spreading practice across separate sessions reliably beats the same amount of practice packed into one sitting (Cepeda, Pashler, Vul, Wixted and Rohrer, 2006). The useful moment to revisit a line is just before it slips away, when recalling it still takes effort but is still possible. Each successful recall at that point pushes the next one further out, so a line you needed daily in week one might only need checking once a month by exam time.
This is not a fringe result. In 2013, a panel of researchers reviewed ten common study techniques for Psychological Science in the Public Interest and rated only two of them as high utility: practice testing and distributed practice (Dunlosky, Rawson, Marsh, Nathan and Willingham, 2013). Highlighting and re-reading, the two most popular techniques in most classrooms, both rated low.
The catch is bookkeeping. Which line of a twenty-line poem is due today? Which definition did you last see nine days ago? Nobody manages that with a paper diary, which is most of the reason the research has taken so long to reach everyday study.
How Memoriee applies this
Memoriee is built around those two high-utility techniques and nothing else. Every practice method is a form of retrieval, from filling in blanked-out words up to typing or speaking the whole passage from memory. When you finish, it checks your attempt word by word and uses the result to schedule the next review, so the lines you struggle with come back sooner and the ones you know drift further out. The scheduling is FSRS, an open-source algorithm that grew out of recent research on modelling memory (Ye, Su and Cao, 2022).
You do the recalling. It does the diary-keeping. Everything you add stays in your browser, and there is no account to create.
If you have a poem, a speech or a page of definitions you need word for word, add it to Memoriee and try a session.
References
Bjork, R. A. (1994). Memory and metamemory considerations in the training of human beings. In J. Metcalfe & A. P. Shimamura (Eds.), Metacognition: Knowing about knowing (pp. 185-205). MIT Press.
Cepeda, N. J., Pashler, H., Vul, E., Wixted, J. T., & Rohrer, D. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354-380. https://doi.org/10.1037/0033-2909.132.3.354
Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., & Willingham, D. T. (2013). Improving students' learning with effective learning techniques: Promising directions from cognitive and educational psychology. Psychological Science in the Public Interest, 14(1), 4-58. https://doi.org/10.1177/1529100612453266
Karpicke, J. D., & Roediger, H. L. (2008). The critical importance of retrieval for learning. Science, 319(5865), 966-968. https://doi.org/10.1126/science.1152408
Murre, J. M. J., & Dros, J. (2015). Replication and analysis of Ebbinghaus' forgetting curve. PLOS ONE, 10(7), e0120644. https://doi.org/10.1371/journal.pone.0120644
Roediger, H. L., & Karpicke, J. D. (2006). Test-enhanced learning: Taking memory tests improves long-term retention. Psychological Science, 17(3), 249-255. https://doi.org/10.1111/j.1467-9280.2006.01693.x
Ye, J., Su, J., & Cao, Y. (2022). A stochastic shortest path algorithm for optimizing spaced repetition scheduling. Proceedings of the 28th ACM SIGKDD Conference on Knowledge Discovery and Data Mining, 4381-4390. https://doi.org/10.1145/3534678.3539081