| Tell me about|
|For our next session...|
|Popping into your mind|
Hermann Ebbinghaus (1850-1909) was a veteran of the Franco-Prussian War and German psychologist who was the godfather of the study of memory in psychology. He was one of the earliest psychologists to adhere strictly to the scientific method. Ebbinghaus's work is important not only for being foundational in memory research, but also for helping to differentiate psychology as a discipline separate from philosophy and establishing early experimental techniques. He opened two psychology labs in Germany, founded an academic journal, and wrote a number of elementary psychology textbooks. Some of his important concepts:
- Use of nonsense syllables. In his memory exercises, Ebbinghaus used nonsense syllables like "MUR" or "DIT" to avoid contaminating experiments by using words with prior associations.
- Learning and forgetting curves. Ebbinghaus discovered that both learning and forgetting follow exponential functions where the law of diminishing returns applies. Recall improves much faster the first few times something is rehearsed and the memory of items fades fastest right after their rehearsal but continue to fade slower over time.
- Savings effect. Ebbinghaus found that items he had forgotten could be relearned faster than brand new items. Thus, memory could somehow be "saved" in the unconscious.
- Serial position effect. This describes how items in a list are remembered. The serial position curve is a u-shaped curve where percent recalled is plotted against the item's position in a list. The left end of the u-shape is higher than the right end. This discrepancy is called the primacy and recency effects. The primacy effect refers to the fact that the earliest items will be recalled the most accurately. The recency effect refers to the fact that the latest items on the list will be recalled the second most accurately. Items in-between follow a parabolic curve. The phonological loop in modern working memory models is based on the serial position effect.
- Differentiating between voluntary and involuntary memory. These definitions are fairly self-evident. Voluntary memory is simply trying to remember something, while involuntary memory is remembering something without trying.
- Persevering in the face of monumental tedium. Ebbinghaus only used himself as a subject. One of his reasons for doing so was that he thought his experiments were too tedious to subject other people to. Some of his exercises included thousands of items and rehearsals.
Ebbinghaus' work was later replicated by many psychologists and these concepts are still basic to research in memory today. He also created one of the first cognitive illusions, the Ebbinghaus Illusion pictured at left.