How to remember what you read

Why you forget what you read

Reading is mostly recognition. Everything is on the page, every sentence makes sense as you pass it, and the whole chapter feels familiar by the end. But familiar isn't remembered. Without any effort to retrieve it, most of what you read fades within days. See the forgetting curve.

Rereading feels like the fix, and it's what most students do. But in a 2009 study by Andrew Callender and Mark McDaniel, reading a textbook chapter a second time added little to what students could answer about it afterwards. The second read feels smoother, which is easy to mistake for learning.

Read, recite, review

In a 2009 study, Mark McDaniel, Daniel Howard and Gilles Einstein tested a simple routine called read-recite-review. Students read a passage, then recited out loud everything they could remember with the text out of sight, then read it again to check. They recalled more of the text, both right away and a week later, than students who simply read it twice.

1. Read one section: a few paragraphs, up to a page.
2. Close the book and recite: say or write the main points, in your own words.
3. Open it and review: check what you missed or got wrong, and reread just those parts.
4. Move on to the next section, and at the end, recite the whole chapter's main points once more.

The recite step is active recall. It's harder than reading, and you'll leave things out. That's the point: the gaps show you what to look at again, and the effort of retrieving is what makes the rest last.

Ask before you read

Before you start, spend two minutes skimming: the headings, the words in bold, the figures and the questions at the end of the chapter. Turn each heading into a question. “Causes of inflation” becomes “What causes inflation?”

Now you're reading to answer something, not just to get to the end, and the recite step is ready-made: you answer your own questions. This is the core of SQ3R (survey, question, read, recite, review), a study method from the 1940s that read-recite-review simplifies.

Recall beats mapping and summarising

In a 2011 study, Jeffrey Karpicke and Janell Blunt had students learn a science text in one of two ways. One group drew concept maps of it with the text in front of them. The other read it and then practised recalling it from memory. A week later, the recall group did better, even on a test that asked them to draw a concept map.

Summaries, highlights and mind maps aren't useless. They're most useful as material to test yourself from later, not as the studying itself. If you make a summary, close it and try to rewrite it from memory the next day.

Speed reading won't help

A 2016 review led by Keith Rayner looked at the research on reading speed. Reading is limited mostly by how fast we recognise words and understand language, not by how our eyes move across the page. When people read much faster, they understand less. Speed reading courses trade comprehension for speed.

Skimming has its place: finding where the important parts are, or deciding whether a paper is worth reading. Just know when you're skimming, and don't expect to remember a chapter you skimmed.

What to recall, by kind of text

Make it stick over the following days

• The same evening, write five questions about what you read. Answer them the next day without the book.
• Turn the key ideas into flashcards and review them with spaced repetition.
• Explain one idea from the chapter to someone, or to yourself. See the Feynman technique.
• Connect it: ask how this chapter relates to last week's, and what would change if one fact were different.

FlashCardz does the question-writing for you. Add the chapter or your lecture slides as a PDF, and it writes questions on the key ideas, each quoting the line it came from, so you can check every answer against the page. Turn a PDF into flashcards.