Hermann Ebbinghaus

Tuy, meb, vaz, mif. No sense, right? What if you memorized 36 of them repeatedly until you got them right while measuring and tracking everything yourself? That, believe it or not, is an experiment by Hermann Ebbinghaus in his memory studies, marking the beginning of his most significant contribution: experimental psychology of memory.

• Who is Hermann Ebbinghaus?

• How did Hermann Ebbinghaus conduct his experiment?

• What did Hermann Ebbinghaus discover in his investigation?

• What is the Ebbinghaus forgetting curve?

• What did Hermann Ebbinghaus theorize about learning and memory?

Hermann Ebbinghaus: Biography

On January 24, 1850, Hermann Ebbinghaus was born to Carl and Julie Ebbinghaus in Barmen, Germany, where he grew up in the Lutheran faith. At 17, Ebbinghaus entered the University of Bonn to study history, philology, and philosophy. In 1870, he temporarily stopped his studies to join the Prussian army when war broke out between France and Prussia. After the war in 1871, Ebbinghaus continued his philosophical studies at the University of Bonn, earning a Ph.D. in 1873.

Hermann Ebbinghaus, commons.wikimedia.org

Gustav Fechner's Elements of Psychophysics drew Hermann Ebbinghaus to psychology, which interested him because of its philosophical and scientific views. His independent studies and memory experiments began in 1878, which led him to publish his groundbreaking book, On Memory, in 1885, where Ebbinghaus popularized the forgetting curve.

More memory experiments, the establishment of experimental psychology labs, and the co-founding of the Journal of Psychology and Physiology of the Sense Organs came in the years that followed. Ebbinghaus also wrote psychology textbooks, The Principles of Psychology and A Summary of Psychology, later published in 1902 and 1908, respectively.

Between those years, Ebbinghaus also taught at the University of Berlin (1883), the University of Breslau (1894–1905), and the University of Halle (1905–1908). Ebbinghaus died of pneumonia in 1909 at the age of 59.

Hermann Ebbinghaus: Psychology Definition

Hermann Ebbinghaus was a proponent of experimental methods and integrated them into his view of psychology. It is also a common theme in his work that psychology is similar to the natural sciences. Ebbinghaus sought to establish this meaning in his research, including his memory experiments.

While others recognized Ebbinghaus's push for experimental psychology, critics such as Wilhelm Dilthey argued that this view of psychology is erroneous because understanding the mind demands experience. Therefore, psychology cannot be descriptive and figured out by logic. In response, Ebbinghaus argued it was wrong for Dilthey to claim that explanatory psychology adheres to the same rule of cause and effect as physics.

Instead, as Ebbinghaus understood psychology, psychology is only meant to describe the causal link in the proximity of two sensations, as the interpretation of one leads to the expression of the other.

Hermann Ebbinghaus: Experiment

Around the same time that Wilhelm Wundt suggested that experimental research is impossible with memory in his Physiological Psychology, Hermann Ebbinghaus sought to counter this as he became interested in studying human memory, mainly forgetting memories. Hermann applied a mathematical component to his study, as influenced by Gustav Fechner's work, to describe the process of forgetting through the forgetting curve.

Memory: Forgetting Curve Experiment

Ebbinghaus made himself the subject of his study, memorizing 2,300 consonant-vowel-consonant nonsense syllables divided into lists, which he created. Ebbinghaus designed this study in a way to see how learning happens without meaning using nonsense syllables and in a way that familiarity with the material won't be an issue.

Hermann Ebbinghaus' method in this memory experiment involved retaining the original order of all the lists of nonsense syllables and memorizing each list at a constant rate. Ebbinghaus would then repeatedly read through the list and make sure to recite the list in its original order while keeping a record of how many trials it took for a perfect recitation of the nonsense syllables. He also looked at how speed, number of repetitions, and the number of words affect memory.

Nonsense syllables examples Hermann Ebbinghaus used in his experiment

Ebbinghaus measured memory retention by comparing how much time it took to memorize the exact words the second time compared to the initial attempt after a certain period and subsequent memorization attempts.

He found that increasing list length (between 7 and 36 words) also increased the learning time initially, but subsequent attempts led to a leveling out of the required learning time. In repetitions, Ebbinghaus found that increased repetitions upon learning the first time reduced the amount of time to relearn after 24 hours.

Ebbinghaus also tested whether subsequent attempts led to easier relearning. He compared six days of learning and relearning three lists of CVCs (12, 24, and 36 words) vs. one stanza made of 80 syllables and found that from initial attempts, the repetitions required for relearning decreased gradually in each subsequent attempt.

Hermann Ebbinghaus: Forgetting Curve

Ebbinghaus developed the forgetting curve to illustrate how human memory declines after learning new information. Not only did Ebbinghaus describe the process of forgetting through a curve, but he also developed a formula represented by:

R = e^(-t/S)

R is memory retention

S is the strength of memory

t is time

e represents the increasing rate of forgetting over time

The red line illustrates forgetting without the attempt to relearn, but with each subsequent relearning, much more information is retained as shown by the green lines, commons.wikimedia.org

The Ebbinghaus forgetting curve shows us that memory declines the sharpest within 20 minutes of initial learning, and then after an hour, our memory loses about half of the new information. After 24 hours, the curve flattens out. Human memory declines if there are no attempts to review previously learned information. Still, Ebbinghaus also noted that difficulty and presentation of material, relevance, stress, and sleep could influence the forgetting curve. According to Ebbinghaus, the leveling of the forgetting curve may indicate increasing memory strength due to active recall of information such as repetition.

Hermann Ebbinghaus: Learning Curve

Hermann Ebbinghaus's learning curve is the same as the forgetting curve in that it has an exponential nature. In the forgetting curve, the sharpest decline occurs within 20 minutes of learning, whereas in the learning curve, the rapid increase happens in the first repetition. Subsequent attempts, however, show an evening out of the curve because memory retention of new information declines after each repetition. The good news is that Ebbinghaus also mentioned in his learning curve that relearning is easier and strengthens memory, thus increasing retention following subsequent relearning.

Ebbinghaus also showed the benefits of spacing effects in learning through his experiments, which means studying information at different times instead of trying to learn it all at once.

Hermann Ebbinghaus: Theory

Aside from Hermann Ebbinghaus's learning and forgetting curve theories, he also put forward more concepts on memory that still prove to be valuable today, especially in memory research and learning. One of which is the “savings” in relearning. Ebbinghaus defined savings in relearning as the amount of information retained from previously learned material despite a lack of recall.

Milk and cookies, pexels.com

Ebbinghaus also introduced the idea of voluntary and involuntary memory. Involuntary memory pops into your head without any prompting from you. The recollection is unplanned, such as when you eat something, and it brings back a childhood memory.

Taking an exam, pexels.com

On the other hand, voluntary memory is the recollection motivated by one's free will. For example, when you're taking your exam, you consciously recall what you've learned.

Another concept that Ebbinghaus introduced is the serial position effects of memory, which he illustrated in yet another curve, which he called the serial position curve.

According to Ebbinghaus' serial position effects of memory, the likelihood of remembering an item on a list depends on its position, with the first and last items usually remaining in memory.

We can see the effects of serial position on memory every day, such as in advertising. The goal of commercials is to leave a positive impression on potential customers by presenting information so that you remember the problem their product solves and their claim of the benefits you can expect from using it.

To-do list, pexels.com

In the serial position curve, Ebbinghaus introduced primacy and recency effects. The primary effect occurs as the first items on the list go to the long-term storage (due to memory rehearsal), making them easier to remember. One example of a primacy effect is when someone gives you a list of things to do and puts the most important things at the top to help you remember them.

Figure skater, pexels.com

Meanwhile, the recency effect occurs due to the last item's storage in short-term memory, making it easier to retrieve and remember. One example of the recency effect is in figure skating competitions. One study₁ found that contestants who took the stage later in the first round scored higher in both the first and second rounds.

Hermann Ebbinghaus: Contribution to Psychology

Ebbinghaus earned an essential place in psychology. Beginning with his memory and learning experiments, he modeled how these cognitive processes can be studied using a scientific approach through his famous forgetting curve. Aside from that, his use of nonsense syllables and the promotion of experimental methods in psychology helped establish a model for further research on cognitive abilities.

Hermann Ebbinghaus, commons.wikimedia.org

Hermann Ebbinghaus's research on verbal intelligence, such as his development of sentence completion exercises, found its relevance and application in psychology, such as memory studies and psychological evaluations. His publications, though few, made a lasting impact on psychology, such as the psychology journal he co-founded, which helped advance the field. Some even regard his dissertation on memory as the catalyst that led to more psychological studies.