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In the early 1880s, the German psychologist Hermann Ebbinghaus memorised lists of made-up syllables such as 'wid' and 'zof', then timed how long it took to relearn each list after different delays. He found that forgetting is fastest just after learning and then slows: most of what is lost goes within the first day.

Hermann Ebbinghaus, Memory: A Contribution to Experimental Psychology (1885)

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The story behind the card

He published the results in 1885 in 'Memory: A Contribution to Experimental Psychology', and his graph became known as the forgetting curve. It was one of the first times a mental process had been measured with numbers rather than described in words. He used meaningless syllables so that no list would be easier because of what it meant, and he was his own only subject. Ebbinghaus also noticed that spreading repetitions over several days works better than cramming them into one sitting, now called the spacing effect; flashcard apps that schedule a review just before you would forget are built on it. In 2015 Jaap Murre and Joeri Dros repeated his method and obtained a very similar curve.

Türkçe oku
Alman psikolog Hermann Ebbinghaus 1880'lerin başında “wid”, “zof” gibi uydurma hecelerden oluşan listeler ezberledi, sonra her listeyi farklı sürelerin ardından yeniden öğrenmenin ne kadar zaman aldığını ölçtü. Unutmanın öğrendikten hemen sonra en hızlı olduğunu, sonra yavaşladığını buldu: kaybedilenin çoğu ilk gün içinde gidiyordu.

Sonuçları 1885'te “Bellek Üzerine: Deneysel Psikolojiye Bir Katkı” adlı kitabında yayımladı; çizdiği grafik unutma eğrisi olarak tanındı. Bu, zihinsel bir sürecin sözle anlatılmak yerine sayılarla ölçüldüğü ilk örneklerden biriydi. Ebbinghaus, hiçbir liste taşıdığı anlam yüzünden daha kolay akılda kalmasın diye anlamsız heceler kullandı; deneklerin tek kişisi de kendisiydi. Tekrarları birkaç güne yaymanın hepsini tek oturuşa sıkıştırmaktan daha iyi sonuç verdiğini de fark etti; buna bugün aralıklı tekrar etkisi deniyor. Bir bilgiyi tam unutmak üzereyken yeniden karşınıza çıkaran kart uygulamaları bu ilkeye dayanır. 2015'te Jaap Murre ve Joeri Dros onun yöntemini yeniden uyguladı ve çok benzer bir eğri elde etti.

Sources and further reading

Background reading: Forgetting curve
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