To study learning as it occurred, Ebbinghaus needed material that had not been previously experienced. For this, he cre- ated a pool of 2,300 “nonsense syllables.” Hoffman et al. (1986) point out that the standard discussion of Ebbinghaus’s syllables is incorrect. It was not his syllables that had little or no meaning; it was a series of syllables that was essentially meaningless. That is, referring to Ebbinghaus’s syllables as nonsense syllables is a misnomer. Many of Ebbinghaus’s syl- lables were actual words, and many others closely resembled words. From the pool of 2,300 syllables, Ebbinghaus chose a series to be learned. The series usually consisted of 12 syllables, although he var- ied the size of the group in order to study rate of learning as a function of the amount of material to be learned. Keeping the syllables in the same order and using himself as a subject, he looked at each syl- lable for a fraction of a second. After going through the list in this fashion, he paused for 15 seconds and went through the list again. He continued in this manner until he could recite each syllable without making a mistake, at which point mastery was said to have occurred.
At various time intervals following mastery, Ebbinghaus relearned the group of syllables. He recorded the number of exposures it took to relearn the material and subtracted that from the number of exposures it took to initially learn the material. He called the difference between the two savings. By plotting savings as a function of time, Ebbinghaus created psychology’s first retention curve. He found that forgetting was most rapid during the first few hours following a learning experience and relatively slow thereafter. And he found that if he overlearned the original material (if he continued to expose himself to material after he had attained mastery), the rate of forgetting was considerably reduced. Ebbinghaus also studied the effect of meaningfulness on learning and memory. For example, he found that it took about 10 times as many exposures to learn 80 random syllables as it did to learn 80 suc- cessive syllables from Byron’s Don Juan.