ABSTRACT
The experimental study of memory was begun in a systematic way by Hermann Ebbinghaus, who published the results of a long series of investigations in 1885. 1 The method introduced by Ebbinghaus was that of committing to memory series of nonsense syllables varying in length and selected by chance. The nonsense syllable was chosen because it possessed the formal characteristics of a word, yet lacked the associations which cause words to mean different things to different persons, and to suggest different things to the same person at different times. The construction of a large number of nonsense syllables, formed usually of two consonants joined by a vowel, supplied a body of fairly uniform material without meaning. The syllables were separately printed on small cardboard squares which could readily be mixed together. A series of any desired length could then be drawn by chance and placed before the observer for learning. The series thus selected was repeated aloud by the observer until he could say it without looking at the cards. Each repetition was re corded by moving a bead from one end of a string to the other. A metronome was employed to control the regularity of repetition; and also to calculate the time required to accomplish the memorizing. The series thus learned was relearned after an interval. In this way the experimenter was able to determine the average length of time and number of repetitions required to memorize series of varying length, and also the average length of time and number of repetitions required to relearn the same series after variable intervals during which the series had not been recalled. The results showed that, although the learner might be quite unable to recognize a repeated series as having previously been memorized, there is a saving in the time and in the number of repetitions of the second over the first learning.
