Spaced repetition: remembering more while studying less
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Studying the night before an exam works for the exam and for almost nothing a week later. Spaced repetition solves exactly that problem: it spreads reviews over time so that what you learn moves into long-term memory with as little effort as possible.
The forgetting curve
In the late nineteenth century, the German psychologist Hermann Ebbinghaus measured how quickly he forgot lists of nonsense syllables. He found that forgetting is very fast at first and then slows down: a lot is lost in the first hours and days, and whatever survives takes longer to go.
He also noticed something more useful: every time he reviewed, the forgetting that followed was slower. A memory reviewed several times lasts much longer than one seen only once.
The spacing effect
Since then, hundreds of experiments have confirmed what is known as the spacing effect. A widely cited review published by Cepeda and colleagues in 2006 gathered more than a century of studies and concluded that spreading study across separate sessions produces better long-term recall than packing it into one.
The most accepted explanation is that recalling something when it already takes a little effort forces the brain to rebuild the memory, and that effort strengthens it. Reviewing something you have just seen feels comfortable but adds little.
How it becomes a system
A spaced repetition system keeps track for you. Every card has its own calendar:
- If you remember it, the next review moves further away: from one day to several, then weeks, then months.
- If you miss it, it comes back soon and the interval shrinks.
- Easy cards almost vanish from your daily routine; hard ones get the attention they need.
The result is that each session is spent almost entirely on what you are about to forget, which is where your time pays off most.
Tips to make it work
- Review every day, even if only for five minutes. Consistency matters more than length.
- Answer honestly. Marking a card you hesitated on as known only postpones the problem.
- Do not add more new cards than you can keep up with. Every new card means several future reviews.
- If you miss a few days, that is fine: pick it up again and let the system reorder what is pending.
In Galigo, reviews are scheduled by the FSRS algorithm, and you simply answer “Again” or “Good” on each card.