First of all, let me give you the good news: stress is not something that blocks our learning. On the contrary, stress is actually a learning accelerator. Under acute stress conditions (for example, if we are scared or even positively surprised), the brain’s neurotransmitter noradrenaline first makes sure to activate precisely those regions of the brain that heighten our attention.1 About twenty minutes later, this action is further supported by the hormone cortisol, which silences the distracting background flurry of nerve cells.2 We are then able to become more focused and concentrate. The conclusion? Under acute stress, we are extremely capable of learning. For example, if we cross the street and almost get hit by a car, we take note of this for future street crossings. This is even the case when we are positively stressed. For instance, most of us will never forget our first kiss—even if we only experienced it once.
When our brain is under stress, our neural network is animated, enabling us to learn more rapidly. However, if the content that is being learned does not have anything to do with our stress, it’s a very different story. The main goal of a brain under stress is to concentrate only on the stress-related relevant information. Everything else becomes unimportant. And this is what makes learning under stress a two-edged sword. When test participants are placed under stress conditions by having their hands submerged in ice water for three minutes while simultaneously tasked with memorizing a list of words, a few days later, they are readily able to recall all of the words having to do with ice water (such as “water” and “cold”), but they cannot remember any of the other arbitrary words (“square,” “party”).3
If you are almost hit by a car, you are able to draw an immediate correlation between looking both ways before crossing the street and possible death. And you will never forget it. But if you are studying Latin vocabulary, you have to stretch your imagination three times as much to establish a connection between the phrase “alea iacta est” and the consequences of bad test scores.
A brief interim conclusion at this point: the brain learns quite well under stress if the main point of the learning has to do with the cause of stress itself. After touching a hot stove only once, we are quick to learn that it was not such a good idea. Stress hormones actively regulate the dynamic of the neurons in order to better retain emotional content (the pain from a hot oven is much more important than what brand of oven it is). This is all about emotions, by the way, not facts.4 Facts, facts, facts are boring. Which leads us to the next learning weakness of the brain.
The memorization weakness
DO YOU REMEMBER the list at the beginning of the chapter? Can you recall even half of it? If yes: I owe you congratulations and respect. How did you go about memorizing this list? If you used mnemonic devices, storytelling, or images to help you to relate the various words, did you realize that you actually increased the amount of information that had to be learned? You made yourself “learn” more than was necessary in order to retain the information. This is a paradox. You might ask an additional question: Why does any of it matter at all? The words on the list are mostly arbitrary and have no relevance or context to you. Why should you be bothered to learn them? Merely because an author demands it of you?
This is precisely the point. Our brain is good at adapting to many different situations, actively adjusting itself, and learning new things, but this doesn’t include raw information such as a few random words, bits of data, or facts. Research shows that the upper limit of objects that can be memorized (without using memory tricks such as mnemonic devices or storytelling) is around twenty. Which is not very much. The list at the beginning of this chapter only takes up 146 bytes on a computer hard drive, while a picture of a zebra could easily take up a million times more space. And yet we prefer to imagine, as in a dream, a zebra with a lollipop wandering through a labyrinth (words from the list) instead of learning each of these four words separately. But why is the brain so bad at saving a few simple pieces of information, such as a couple of words?
The reason once again has to do with the way the brain works. The brain doesn’t learn information by rote and then save it somewhere. Instead, it organizes knowledge. There’s a difference. Let me give you a simple example to illustrate. I could list off to you the exact sequence of goals (and who scored them) from the historic semifinal in the 2014 World Cup soccer game between Germany and Brazil that ended in a score of 7–1: 11th minute: 1–0, Müller; 23rd minute: 2–0, Kroos; 24th minute: 3–0, Kroos . . . Okay, I’ll spare any Brazilian readers the rest of the list and get to the point. Once you have assembled all of the data from this game, what do you know about the game itself? Not much, since you are not witnessing the shocked expressions of the Brazilian team or the joy of Philipp Lahm, the German team captain. The significance of the game cannot be derived merely from the combination of data. Only after you have watched the game can you understand why the Brazilians still grumble about it—in spite of their later “revenge” on Germany in the 2016 Summer Olympics.
Massed learning
UNFORTUNATELY, MANY METHODS for learning (whether in high school, at the university level, in vocational training, or continuing education at the workplace) continue to rely on the basic concept that memorizing facts and data is a good idea. On the contrary, this method leads to a completely false strategy for learning, known scientifically as “massed learning,” in which you must pump yourself full of information in a short period of time in the hopes of retaining as much as possible in the future. This obviously doesn’t work, since our brain thinks data packets are totally uninteresting.
An orchestra doesn’t learn a new piece of music merely by playing a single note for one second and then waiting before processing the next informational packet (the next note) and so on for thousands of notes (this would be akin to “massed learning”). No, it learns best by quickly recognizing the relationship between the notes and the way in which, at a certain time and place, they develop into a whole melody.
The context is what allows us to learn effectively—namely, that we do not have to consciously concentrate on the idea that we are learning. This became evident in a study conducted by the work group of my colleague, Melissa Vo, who researched memory capacity among adults. Specifically, the study’s adult test subjects were asked to find objects that were pictured in an apartment setting (i.e., the soap in the bathroom). Although participants were not asked to remember these objects, they were much better able to recall them later than if they had been asked to memorize isolated pictures of the objects.5 When the same objects were isolated and presented to participants in front of a neutral background, the information was much less interesting to participants and thus not saved. A bar of soap makes much more sense in the context of a bathroom than surrounded by a green background. The object by itself is not interesting. It is only its situation in a particular context that gives the object a meaningful correlation, which we do not forget. Though this may seem illogical because it implies that we are required to note down additional information (namely, the object’s surroundings), this is, in fact, an ability that comes easily to us.
The lasagna-learning rule
IN ORDER TO understand this correlation of context and of the meaning of a word, the brain must learn differently than it might be used to—namely, with interruptions. In the last chapter, you already read that the brain sacrifices some pieces of memory to nonmemory (or even actively forgets them) in order to be able to actively combine them. Something similar takes place with learning. Learning is successful when breaks and distance are built into the process, a practice referred to as “spaced learning.” This would seem to go against our better intuition, as we assume that we will only be able to grasp correlations