But our brain? It does exactly the opposite, eluding this goal. A lot of people imagine how wonderful it might be if the brain functioned like a mistake-free computer. How concentrated, quick, and efficient we would be at solving problems! And it’s true: computers don’t make mistakes, and if they do, they crash. But brains don’t crash (unless there is outside help, but that’s another story). This is because the brain works in a completely different way. It is our errors and our inaccuracies in thinking that, in fact, make us superior to computers. All of the horror stories predicting that computers will soon seize the world, leaving us behind in their intellectual shadow, are clearly rejected by biology. In fact, biology seems to contradict the trend of digitalization, that buzzword of our modern times that seems to want school classes networked like businesses, data exchanged and efficiently analyzed. “Classrooms of the Future,” “Analyzing Big Data,” “Deep Learning”—there is no area of our lives that we don’t wish to optimize with the computational power of the machine. The grand ideas of the future, however, will not come from digital, but rather from analog thinking. From brains, not smartphones. Computers might learn things—but we understand them. Computers follow the rules—we can change them.
Computers might be able to beat us at chess or go, but this is neither surprising, creative, nor a cause for concern. I would, however, start to get worried if a computer began making mistakes and then signaled: “Chess? Er, no, I don’t really want to actually, that’s boring. What I’m really in the mood for is a round of World of Warcraft!” Until that happens, the human brain will remain the measure of all things. Precisely because it supposedly functions so poorly.
In this book, I would like to show you what goes on behind the scenes of the probably most erroneous thinking structure in the world (the brain). To describe the way in which the brain uses errors in order to orient itself in the best possible way to its social situation, to think of new ideas, and to generate knowledge. Yes, it makes mistakes in the process, but the paradox is this: it is through our faults and lack of concentration that our most powerful thoughts are generated. Most of our supposed intellectual disadvantages have enormous advantages. The fact that we can’t remember names right away is essential in allowing us to develop dynamic memories. Our propensity to be easily distracted helps us to think creatively. And our tendency to arrive late to an appointment because we misjudged the time is a fabulous thing, because if our inner clocks were exact, we would not be able to jump from memory to memory as quickly as we do but would be trapped in a state of static recollection.
Now, this book is not meant to heap exclusive praise onto all of our intellectual weaknesses. Not every error has a silver lining. But being able to recognize why a brain sometimes doesn’t function at the push of a button is the most important step toward understanding these weaknesses. It can help us to become more focused in decisive moments, to allow for the free flow of creative ideas, or to better retain memories. The brain is most likely the best example of turning weaknesses into strengths.
PS Ah, yes, like any other product of the brain, this book is also subject to biological weaknesses and is thus not error-free. You’ve probably already noted a typo or two, misspellings, or numerical errors that may have slipped in. But after this reading, you will understand why this isn’t so bad but rather a good thing. As long as it’s in moderation. And speaking of moderation, there were twenty-seven M’s in a row a few pages ago. If you managed to count the correct number the first time around, you must really have an error-free brain. Which, at times, also isn’t such a bad thing.
1
FORGETTING
Why You Won’t Remember the Contents of This Book—Thereby Retaining the Most Important Information
DON’T BE SCARED. I am going to give you a pop quiz right at the beginning of this book. I want to be certain that you, dear reader, are paying attention. Here goes: What were the first three words on the previous page? Okay, that’s not a very easy question, no worries. But perhaps you can answer this: What were the first three words of the introduction? And if that’s still too hard: What is the title of this book? I’ll bet you can answer that. If you responded by saying, “Scatterbrain,” well, at least you’ve shown the strength of ingrained language patterns.
In any case, isn’t it astounding? You sharpened all of your senses and focused in order to start reading (at least, I hope so). And yet you cannot remember something you read only two or three pages ago, or else are only able to do so after an intensive round of thinking. Sometimes your thoughts wander or sometimes you are concentrating so much on what you are reading that you forget what you had read only moments before. This will happen throughout the book, regardless of how hard I try to make the text as captivating as possible. As an author, I’m naturally happy if the reader can retain every tidbit that I’ve laboriously tapped out on the keyboard. But as a neuroscientist, I am also aware that humans rarely remember what they’ve read. Hardly anyone is going to be able to recall, word for word, the contents of this book by the end. (Although, if that does happen to you, please contact me. Help and the Guinness Book Committee will be on their way.) You should, however, be able to recall the primary message of each chapter. Hopefully. If not, please buy the book again in order to read it from the very beginning, newly cracked open and smelling of fresh ink. That would make me happy, too.
Apparently, the brain is in a permanent state of forgetting. Anyone who has driven a longer stretch in a car knows what I am talking about. You’re driving nonchalantly along the road and then you pause after an hour and ask yourself, “Where am I, actually?”—as though you had somehow switched on a mental autopilot that blocked your memory. Who needs a self-driving Google car when our brains have already mastered the art of autonomous driving? The fact that we don’t recall much about a journey through the landscape may have one of two causes: Firstly, the surrounding terrain may have been exceptionally boring (anyone who has driven through Kansas on the I-70 knows what I mean). Or secondly, the brain decided it should simply delete most of the information from the previous sixty minutes. The latter case is the default setting of our thought organ.
This isn’t such a bad thing when we are driving a car. But there are other situations in which our brains don’t notice a lot. What was last night’s newscast headline? What were you thinking about last night before you went to sleep? Did you really lock the door? Question after question that the brain does not want to answer. What an incredibly slipshod organ! Always forgetting, deleting, and blundering. But why is that? Why doesn’t the brain remember more than it does and why does it seem to wipe out so much information?
Whether it is dealing with banal everyday topics or really important information, the brain discards everything with the same mechanism. In this age of media overkill, we get used to short-term thinking and are constantly bombarded by new information and messages. Articles that we skim but don’t retain. News items that we come across in our smartphone apps but soon forget about. Emails that drown in a flood of messages. Never before in history has it been possible to attain so much new knowledge, and never before has it been so complicated to keep hold of what is truly important. What is going on in our brain when we forget something that we just experienced? And what can we do to not to let the most important bits slip from our memory once again?
A dressing room for memories
FIRSTLY, LET ME reassure you: you shouldn’t worry too much if you were unable to remember what was written two pages ago. It is not your brain’s job to save as much information as possible. Of much more importance is that the brain forgets the right things at the right time, deleting them from consciousness. Memories are not static; they aren’t data bits that can be accessed once the brain has uploaded them. Rather, memories are dynamic and constantly changing. Only in this way is it possible for the brain to generate new knowledge.
In order for this system to continue, your brain has become an expert at throwing things away to keep them from distracting you. The discarded information might be sensory perceptions, as well as memories, new information, or impressions. In order to maintain as flexible and adaptable a recollection as possible, the brain must eliminate as much information as possible. Only that which is very important is allowed to enter our consciousness, ensuring that we may