Scatterbrain. Henning Beck
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for the brain. It’s like the technique that memory experts recommend, of imagining images or stories to correspond with words or phrases in order not to forget them. Something similar occurs automatically in our brain—and sometimes it goes a little too far.
If you want to research human memory errors under standardized scientific conditions, you somehow have to create these errors artificially. One tried and tested method of choice is a test named after its developers, Deese-Roediger-McDermott, or DRM for short. Test subjects are first shown a selection of terms, which they are asked to memorize quickly. For example, read the following list two or three times thoroughly:
Truck, street, drive, key, garage, SUV, freeway, accelerate, gas station, bus, station wagon, steering wheel, DMV, motor, pass
DRM researchers do this with several lists and then give the test subjects time to think or else distract them with a different focused exercise. In order to do this with you, I will simply continue writing this sentence, adding in an unnecessary clause here, and putting something completely unimportant (irrelevant) into parenthesis over there, all in order to move you a bit further away from the list. Don’t look back! Please move on to the top of the next page!
Your task: which of the following word(s) did you see in the previous list?
Steering wheel, car, seat, motorcycle, inspection
Alternatively, I could ask you to write down which words you remember and then compare the lists to see which words match and which words you may have added. By now you have realized that this is a simple variation of the puzzle that I gave you at the start of the chapter. Interestingly, by setting up a carefully devised experiment (one that is not as limited as I necessarily am in the confines of this book), it is possible for researchers to get 80 percent of test subjects to claim that they “recognize” false words, or to put it another way, to facilitate the production of false memories.5
The reason behind this weakness of memory lies in the manner in which information is integrated into the brain from the very beginning. When you read a word, you first receive it in the image-processing region of your brain, which is located in your neck area. However, in order to grasp the contents of the word, it must be semantically processed—that is, to relate the new word’s meaning to other words with similar meanings. This takes place in the frontal cortex, or more specifically, in the front and side area of your frontal lobe (for those who must know exactly: the ventrolateral prefrontal cortex). Studies show that both true and false memories are generated in an almost identical fashion. Although true memories do tend to show increased activity in the image processing region—since one is closer to the raw information from one’s surrounding environment—the further processing stages in the brain are more or less the same for false memories.6 Or, to put it another way, not only do we perceive a list of words, we shape the perceived truth. We endow it with a meaning and pack the concepts into a mental box.
In chapter 11, we will explore the consequences of excessive inside-the-box thinking or pigeonholing, but for now, allow me to make one remark: invented memories are created in the same way as true memories. Of course, false memories cannot boast the same level of “real” sensory experience, but they are nonetheless integrated into the exact same network. Once this has happened, even if only a single time, it’s too late. The brain can no longer distinguish the false memory from the true one. From that moment on, it doesn’t make any difference to the brain what is fantasy and what is reality. Or, to quote the neuroscience film classic The Matrix, “Your mind makes it real.” Regardless of whether or not the experience ever really took place. In principle, our memories live in a dream world of our own creation.
Before we slide down the rabbit hole of a fundamental philosophical-epistemological debate, let’s return to the brain’s process of memory formation. A process which is not only influenced by our habit of arranging new information in patterns and boxes but also by our emotions and by fellow human beings.
The emotional traps
We are not only prone to making mistakes when trying to recall lists of words; we also err when we need to put them into a social context. At the end of the day, a piece of information by itself is not the important factor. It also matters to whom, what, when, where, why, how it was said. Researchers have studied this by showing test participants various videos. In one video, a person speaks directly to the participants, and indirectly in the other video, by looking off to the side of the camera lens. This has an apparent effect on participants’ memories—not of the contents of the words spoken (which they are able to recall well under both circumstances)—but of the conversational situation. Most participants falsely recall having been directly addressed in the video, even when they were shown the video with the person speaking indirectly.7 While the hippocampus (if you recall, the memory center of the brain) was busy saving the contents correctly, a neighboring region of the brain, the anterior cingulate cortex (ACC), was responsible for the incorrect memories of the conversation and was excessively active in creating the false memories. We seem to take in information subjectively which we also do not save objectively.
To add insult to injury, emotions can lead to memory distortions as well, even in a simple DRM test. For example, if study participants are placed under emotional stress, such as giving a speech in front of an audience or having to take a terrible math test before they are instructed to memorize a list of words, they end up generating a large number of false memories.8
However, not all emotions have the effect of misleading our memories. Those types of emotions particularly predisposed to distort our memories tend to have two traits in common: the emotions are intense, and they also appear to match the information that we are supposed to remember. So, if we are in a good mood, we are more prone to falsely remember words from positive vocabulary lists. If we are in a bad mood and stressed out, it’s more likely that we will confuse lists of negative words.9 The best option would be to always be in a good mood when driving a car because this would enable us to be the perfect witness to traffic accidents. Although . . . research has pretty clearly shown that no one makes for a very good witness to an accident. This is due to another memory-related weakness of the brain.
The perfect memory crime
NOT ONLY DOES our brain have problems saving information, it also struggles to consolidate and retrieve the information from memory since it is susceptible to all kinds of misinformation, which it gladly accepts and adds to the previously existing memory. Our memory is thereby no longer true, though it may seem more coherent.
Just imagine, for example, that you are sauntering down the street when you suddenly hear the sound of squealing tires! You can only guess where the noise is coming from and you turn to look just in time to see two cars crashing into each other. Naturally, you voluntarily offer yourself as a witness to the scene, and this is where the problems start. You only really “half” experienced the crash. You believe you saw how the cars drove into one another, but you aren’t quite certain. It all happened so quickly. The brain really dislikes being in a condition of uncertainty (experts call this “cognitive dissonance”), and it is always trying to create a coherent overall picture. If what you perceived is fragmented, the brain will substitute in the rest of the information without you even noticing. Incidentally, this is the same brain that both generates a seamless consciousness and recalls false memories, so you also won’t be able to trace the origins of the false memories. In other words, it is the perfect memory crime story—in which the perpetrator (your brain) and the detective (your brain) are one and the same. Both players have very little interest in an explanation, meaning you won’t even think twice about the false memory.
Imagination is learning too
OKAY. SO, IF this is true, how should our brain be able to figure out which memories are true? Because the brain does not have any “criteria for truth,” it uses a trick in which it only classifies information as real if it activates a large portion of the brain. In other words, if something really did happen, it must have left large tracks of activity across the network. This is true in principle since authentic experiences trigger particularly intensive brain activity. If we merely imagine a photograph, the image processing areas of our brain are