Hermann Ebbinghaus Experimental psychologist. Date of Birth: 24.01.1850 Country: Germany

1. Herman Ebbinghaus: Biography of a Psychologist-Experimentalist
2. Experimental Methods and Material
3. Methodology and Measurement
4. Experimental Constraints and Results

Herman Ebbinghaus: Biography of a Psychologist-Experimentalist

Herman Ebbinghaus was a renowned psychologist-experimentalist who became famous for his work on memory. He is best known for his groundbreaking publication "Über das Gedächtnis" (On Memory), which marked the first original and highly fruitful attempt to apply experimental methods to the study of mental phenomena in its own sense. Ebbinghaus aimed to investigate the conditions of mechanical memory. To achieve this, he conducted experiments on the learning and reproduction of material that lacked any logical connection.

Experimental Methods and Material

In his experiments, Ebbinghaus used meaningless sequences of syllables as the material for learning. To ensure equal difficulty in memorization, all syllables were constructed according to the same pattern. Each syllable consisted of three letters: a vowel in the middle with two consonants on either side (e.g., bar, vis, get, etc.). The sequences were arranged in such a way that adjacent syllables did not form any recognizable words or phrases. New syllables were introduced into the sequences until their supply was exhausted (up to 2300 syllables). When the supply ran out, the syllables were shuffled, forming new sequences.

Methodology and Measurement

Ebbinghaus employed various techniques to measure the learning process. He read the syllables aloud, following a specific rhythm, accentuating known syllables and regulating his speed. Initially, a metronome set the rhythm, later replaced by the sounds of pocket watches. A sequence of syllables was considered memorized when it could be reproduced from memory without error or hesitation. To determine the number of repetitions needed for memorizing a particular sequence, Ebbinghaus used a string of beads, similar to a rosary, moving one bead after each repetition. The number of moved beads indicated the total repetitions made.

Experimental Constraints and Results

Ebbinghaus set specific limitations for his experiments to isolate the influence of mechanical memory. The experiments were conducted over two years, from 1879 to 1880 and 1883 to 1884, with each series of experiments starting and ending at the same hours. His main goal was to examine the dependence of mechanical memory on four conditions: the volume of material learned (number of syllables), the number of repetitions, the time interval between learning and reproduction, and the method of constructing syllable sequences.

Ebbinghaus discovered several key findings from his experiments:
1. As the volume of material increased, the amount of work required also increased, but not in direct proportion.
2. Within 64 repetitions, the retention of learned material after 24 hours was approximately one-third of the initial work. Over time, the forgetting process initially occurred rapidly but gradually slowed down.
3. Association between syllables or facts during learning occurred not only in a direct manner but also in a reverse manner, including both adjacent and non-adjacent syllables.

These findings were further corroborated and expanded upon by the works of Müller and his students - Pilzecker, Schumann, Jost, and Stevens. Among Ebbinghaus' other notable publications, "Grundzüge der Psychologie" (Principles of Psychology) deserves attention for its contribution to the field.