The scientific study of memory began in the early 1880s when a German philosopher, Hermann Ebbinghaus, came up with the revolutionary idea hat memory could be studied experimentally. In doing so he broke away from a 2,000-year-od tradition that firmly assigned the study of memory to the philosopher rather than to the scientist. He argued that philosophers had come up with a wide range of possible interpretations of memory but had produced no way of deciding which among these theories offered the best explanation of memory. Ebbinghaus aimed to collect objective experimental evidence of the way in which memory worked in the hope that this would allow him to choose between the various theories.
Ebbinghaus decided that the only way to tackle the complex subject of human memory was to simplify the problem. He tested only one person, himself, and since he wished to study the learning of new information and to minimize any effects of previous knowledge, he invented some entirely new material to be learned. This material consisted of nonsense syllables, work-like “consonant-vowel-consonant” sequences, such as WUZ, CAX, TU and ZOK, which could be pronounced but had no meaning. He taught himself sequences of such words by reciting them aloud at a rapid rate, and carefully scored the number of recitations required to learn each list, or to relearn it after a delay had caused him to forget it. During his learning he carefully avoided using any associations with real words, and he always tested himself at the same time of day under carefully controlled conditions, discontinuing the tests whenever “too great changes in the outer or inner life occurred.” Despite or perhaps because of using this rather unpromising material, he was able to demonstrate to the world that memory can be scientifically investigated, and in the short period of two years was able to show some of the fundamental characteristics of human memory.
To assess any system’s capacity for storing information, three basic questions must be answered; how rapidly can information be fed into the system, how much information can be stored and how rapidly is information lost? In the case of human memory, the storage capacity is clearly enormous, so Ebbinghaus concentrated on assessing the rate of input and, and of forgetting.
Consider the rate at which information can be registered in memory. If you spend twice as much time learning, do you remember twice as much information? Or is there perhaps a law of diminishing returns, with each additional learning episode putting a little less information into storage? Or perhaps the relationship is the inverse; the more information you have acquired, the easier and quicker it is to add new information rather like rolling snowball picking up more snow with each successive revolution. Ebbinghaus investigated this problem very simply by creating a number of lists each containing 16 nonsense syllables. On a given day, he would select a fresh list (one he had not learned before) and recite it at a rate of 2.5 syllables per second for 8,16, 24, 32, 42, 53 or 64 repetitions. Twenty-four hours later he would find out how much of the list he had remembered by seeing how many additional trials he needed to relearn the list by heart. To get some idea of what his experiment was like, try reading the following list of nonsense syllables as rapidly as you can for four successive trials JIZ, BAH, FUX, YOB, SUR, XIQ, DAJ, LEM, VUQ, PIL, KED, WAV, TUK, GEF.
The results of this very tedious exercise were recorded. The relationship between the number of learning trials in Day 1 and the amount retained on Day 2 has a linear relationship, signifying that the process of learning shows neither diminishing returns nor the snowball effect, but obeys the simple rule that the amount learned depends on the time spent learning. If you double the learning time, you double the amount of information stored. In summary, as far as learning is concerned, you get what you pay for. This relationship has been explored extensively in the 100 years since it was discovered by Ebbinghaus and is known as the total time hypothesis. This is the basic relationship that underlies the whole of human learning.
The generalization that “you get what you pay for” is a reasonable rule of thumb, but within this broad framework there are goody buys and bad ones, bargains and items which are not worth the price tag. Despite the general relationship between practice and the amount retained, there are ways in which one can get better value for time spent. With proper study and memorization techniques, there are ways to beat the total time hypothesis. With memory training, you can actually spend less time studying and get better results and improve your memory. The human mind, as later studies will prove, have an insatiable appetitive to learn new things.