Scatterbrain. Henning Beck
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applied to new situations. Only humans are able to do this. When a “deep learning” computer analyzes millions of images, it will, doubtless, be able to recognize that a chair is most likely an object with four legs, a flat surface, and a backrest. But for us, a chair is not so much an object with a particular shape as it is something to sit on. Once we have understood this, we suddenly see chairs everywhere and can even apply our knowledge to invent, develop, and design new chairs. For example, I recently had one of those bouncy yoga chairs at home. My little neighbor remarked, quite correctly: “A ball!” But when I went over and sat on it, he said: “Oh, chair!” Try teaching that to a computer.
3
MEMORY
Why a False Memory Is Better Than None at All
ON OCTOBER 14, 1994, Tom Rutherford’s world collapsed. He was forced to resign from his career as a minister in the Assemblies of God church because his daughter accused him of sexual assault. The twenty-one-year-old daughter credibly asserted that she had been abused multiple times between the ages of seven and fourteen. She claimed that she got pregnant and was forced by her father to have an abortion with a clothes hanger while her mother looked on. Just imagine! Rutherford lost his job, his friends shunned him, and he had to piece his life together with whatever jobs he could find. One year later a new truth was revealed: his daughter was a virgin. Her vivid memories of abuse only surfaced when she had begun visiting a talk therapist for the purpose of stress management. Over the course of more than sixty sessions and through a question and answer game, Beth Rutherford developed a false memory that had never before existed. The situation was not necessarily deliberate, but was undertaken with the best intentions to help the young woman work on past stress factors. However, at some point, she was unable to distinguish her rampant fantasy world from reality. It was only when a gynecological report left no doubt as to her virginity that Tom Rutherford’s daughter recanted her statements. She subsequently sued her therapist for a million dollars in order to raise public awareness of the danger of false memories.1
I’ll admit—the Rutherford situation is an extreme case. However, three-fourths of judicial errors can be traced back to false testimonies.2 People make claims of having become pregnant under satanic rituals, although they never were pregnant.3 An accused person can remain behind bars for decades due to witness claims that they were spotted at a murder scene until a DNA test finally shows that someone else was the perpetrator.4 These scenarios all represent a nightmare that is nonetheless reality, since most of the prosecution witnesses in question were not aware that their memories had gotten out of hand. A classic lying test would not have been able to detect such false memories because, for the witnesses, their statements did not feel false. This is one reason why eyewitness accounts should be handled with utmost caution.
Not only judges, but historians also have their jobs cut out for them in assessing the truth behind the claims of contemporary witnesses. There is still a raging debate about whether or not low-flying fighter planes shot at civilians during the bombing of Dresden, Germany, in 1945. Dozens of Dresdeners claim to remember such scenes from their youth. However, in the firestorm of the bombardment, low-flying maneuvers were hardly feasible over Dresden and were also not recorded in any military reports. The case pits living narratives against dry deployment reports. Who are you going to believe?
Evidently, we are prone to distorting our memories. “That wouldn’t happen to me!” you might say. “I am perfectly aware of what happened.” But it’s not that clear-cut. Take this example: Do you roughly remember the list from the previous chapter? Don’t flip back and cheat! Now, I am going to give you four words but only one of them was in the original list. Which was it?
Sleep
Phenoxyethanol
Blueberry
Submarine
Okay. We can rule out submarine. And phenoxyethanol. What about the other two words? Think about it, try to picture the list. Which one do you pick: sleep or blueberry?
You are naturally clever enough to realize that none of the words were in the original list. But most people would spend some time going back and forth between sleep and blueberry, or else decide with absolute certainty that it was blueberry. The word seems to be the best fit.
I’ll admit that I knowingly led you astray, as I falsely informed you, firstly by stating that one of the words was in the original list. On top of that, the original list had a few key words (dream, night, strawberry, raspberry) that could cause you to draw associations between the target words “sleep” or “blueberry.” And to add insult to injury, the two contrasting words (phenoxyethanol and submarine) made the remaining words seem more plausible. Perhaps these factors influenced you to create a false memory and believe you could remember the word blueberry on the list. But don’t kick yourself too hard. In the following pages, we are going to learn why this is not such a bad thing, but is instead another one of the brain’s strengths.
The memory chapel
AT THIS POINT, I would like to appeal to your memory of the previous chapter (this time without any ploys or gimmicks). Namely, that information and our brain’s memory content are not static but rather malleable components. We don’t go around recording our minute-by-minute experience of the world with a video camera and then save the film for the rest of our lives. It is much more likely that we are continuously tinkering with our memory, which is itself a dynamic construct.
Memory is dynamic because it can change quickly. Let me return one last time to the orchestra comparison from the last chapter. In the same way that a piece of music can be varied by how it is played by an orchestra, a piece of information in the brain can also be changed. In addition, an orchestra might have fewer or more musicians playing (or neurons, in the case of the brain), in which case the basic concept of the piece of music (the information) remains the same, but the sound would change.
Our memory is a construct because we do not, strictly speaking, call up a single memory when we remember something. Instead, we recreate it new each time, the way that an orchestra plays the same piece of music again but always somewhat differently than before. Each concert—each recollection—is a unique experience. Once our neurons have stopped activating the corresponding memory, the specific memory is gone though it is still saved in our memory. In an orchestra, this memory would be like the ability of orchestral musicians to listen to each other, to play their instruments at precisely the right moment, and thereby be attuned together. In the brain, information is stored among the neural contact spots so that it can be triggered and recreated again in the future. A memory is thus the ability of the neural network to generate a state of activity (corresponding to a piece of information, a thought, or a memory).
In order for an orchestra to play a new piece of music, or for a neural network to save a new piece of information, three steps must be taken. First, the musicians play the new song for the first time, then they practice it, thereby improving their coordination with each other so that they can finally be ready to play it at a concert. Of course, it is important that the orchestra plays the notes with as few mistakes as possible. And this is where a brain is different from an orchestra. A brain doesn’t play the order of notes as they are written on the score but instead alters the melody a little bit each time it practices. The brain’s goal is not to play (or to activate) something that has been predefined because there is no conductor. It is much more important that the brain plays in such a way that the song flows and that it provides a coherent overall feel while at the same time saving as much cell energy as possible. What this means, however, is that the information changes over time, and the more often it is worked on, the more it will change. Our memory is thus contestable at every step: when it records, when it consolidates, and when it recalls past memories.
The vulnerability of memory
IT IS POSSIBLE for a memory to be altered right from the moment when we are learning and saving a piece of information. This is often due to the fact that information is more easily processed when it can take up as many areas of the brain as possible. In order to better solidify a memory,