Spaced Repetition
Spaced Repetition
The practice of scheduling review sessions at progressively expanding intervals, timed against the Ebbinghaus Forgetting Curve so each retrieval attempt happens near the point where the memory is starting to fade — not before, not after.
The "R" in TRAP Framework.
Why timing is the whole game
Per Martin Schneider in How To Learn Anything So Fast (theMITmonk):
"Review too soon and the brain does not have to work hard so nothing durable gets built. Wait too long and you're rebuilding from rubble. Almost nobody hits that window well just by instinct alone."
Two failure modes bracket the goal:
- Too early — review is trivial; no Desirable Difficulties surface; consolidation doesn't happen.
- Too late — content has decayed too far; you're re-learning, not reviewing.
The tractable interval window is narrow enough that humans can't hit it reliably without scheduling support — which is the whole product thesis of Remnote / Anki / SuperMemo.
The default schedule shape
Roughly: 1 day → 3 days → 7 days → ~3 weeks → ~2 months → ~6 months. Each successful retrieval extends the next interval. Adaptive schedulers (modern apps) tune intervals per-card based on recall difficulty.
Where it fits with retrieval practice
Spaced repetition presupposes Desirable Difficulties — each scheduled session is itself a retrieval attempt, not a re-read. The two ideas compose: retrieval practice says how to review (close source, recall cold); spaced repetition says when.