How do you remember more of what you read?

You finished a novel last year, loved it, and today can remember the cover, the mood and one scene with a dog. That is not a personal failing. It is how memory works for almost everyone, and reading would be a very odd hobby if its only purpose were to store information.

Still, there are easy ways to keep more of the good stuff.

Forgetting is the default

The German psychologist Hermann Ebbinghaus spent the early 1880s memorising lists of nonsense syllables and testing himself on how quickly he forgot them. He published the results in 1885 as Über das Gedächtnis, and his "forgetting curve" describes memory fading steeply when nothing is done to keep it, as Wikipedia summarises. A 2015 replication by Murre and Dros found results similar to his.

A novel is not a list of nonsense syllables, and the curve was not drawn for stories. But anyone who has tried to recount last summer's holiday read knows the general shape: without any effort, detail fades and the gist remains. Knowing this takes the pressure off. You do not need to remember everything; you need to decide what is worth keeping.

Retell it

The single most useful habit is also the most sociable one: tell someone about the book. Over dinner, in a message, at the bar. Trying to explain what happened and why it mattered forces you to pull the book back out of memory, which is exactly what helps it stay.

Psychologists call this the testing effect, or retrieval practice: spending some learning time recalling information, rather than just reviewing it, tends to improve long-term memory, according to the research summarised on Wikipedia. The same summary notes that self-testing usually beats rereading or highlighting. You do not need flashcards for a novel. A friend who asks "so what was it about?" does the job beautifully.

Write three lines when you finish

When you close a book, write three things before you start the next one:

• What it was about, in one sentence of your own.
• One moment or idea you want to keep.
• What it made you think of: another book, a person, a place.

That is it. On paper, in a notes app, inside the back cover. The point is not the record, it is the act of recalling and putting it in your own words. If you enjoy it, the habit grows naturally into a commonplace book.

Mark as you go, lightly

A pencil tick in the margin, a folded corner, a sticky tab: whatever you are comfortable with (we argue the case on writing in books). The marks are useful later, when you flip back through and the book comes flooding back. Keep it light, though. Underlining half of every page makes reading slower and the marks meaningless.

Space it out

The same research suggests that recalling something again after a gap, rather than all at once, makes memories more durable. For reading, that can be as simple as looking at your three lines a month later, or mentioning the book again when someone asks for a recommendation.

Reread the ones that matter

Rereading a favourite every few years is the most pleasant memory technique there is, and you notice things you missed the first time. More on that on whether rereading is worth it.