The gift of forgetting
Who hasn't wished at least once for a perfect memory? Are there really people who possess one? And if so, would their lives really be enviable? Case studies show that forgetting can actually be a blessing.
Scientific support: Prof. Dr. Tobias Bonhoeffer
- Case studies show that extremely good memory only applies to a portion of experience.
- People with extremely good memory sometimes suffer from it.
- Forgetting has a function: it helps us focus on important information.
What would it be like to remember everything – every day, every moment, every gesture and word? Author Jorge Luis Borges depicted such a life in his story "The relenteless memory." A young Indian named Ireneo Funes is thrown from his horse and becomes unconscious. When he awakens, he has become lame, but his memory has undergone a fantastic transformation. From this moment on, he can remenber everything in its tiniest detail: "He knew exactly what form the southern clouds assumed at sunrise on April 30, 1882, and could compare them with the grain of a fragment of parchment he had seen only one time, and with the lines of spray that had been cast by an oar on the Rio Negro on the evening before the battle of Quebracho."
Do such miracles of memory really exist? We have all heard of people with a "photographic memory," whose brains apparently record every detail of an experience. "Eidetic memory," as researchers call it, comes from the Greek word "eidos" – for "the form of what has been seen." But in reality it is hard to find people who possess it.
The man with nearly perfect memory
It's no wonder, therefore, that the most famous example lies decades in the past: Solomon Shereshevsky was a Russian journalist and memory master who became famous in the 1920s. Alexander Lurija, a neuropsychologist, met him in Moscow, accompanying and studying Shereshevsky for three decades. In "A small portrait of a huge memory," Lurija preserved an account of the journalist's feats of memory. In 1934, for example, Lurija presented his subject with a long, complicated and meaningless mathematical formula. Shereshevsky studied the formula for seven minutes and was then able to reproduce it without a mistake. Fifteen years later Lurija asked him to reproduce it again, and he did so – again without error.
"It's obvious that this man had a far better memory than a normal person," says Psychologist Douwe Draaisma of the University of Groningen in the Netherlands. Shereshevsky was special for another reason as well: he experience synesthesia – in other words, sensory impressions came to him in a mixture. This might at least partly explain the performance of his memory. "For a person with synesthesia, a word might be accompanied by a color or a tone that it is associated with," Draaisma says. "If such a person is presented with a list of words to remember, they can do so using more than one sense, and this is a great help."
Shereshevsky wasn't a genius at all types of memory: his recollection of faces or voices was rather poor. "Such extreme cases of memory retention usually develop only in a particular area," Draaisma says. "A person might have an extremely good memory for music, but not at all for faces. Another person might remember patterns, but not experiences."
Good memory as an isolated gift
Such isolated talents also appear in savants: people who suffer from autism or another form of developmental disorder but have extreme abilities in a particular area. Kim Peek, the inspiration for Dustin Hoffmann's character in the Hollywood film "Rain Man," had a mental disability due to a rare chromosomal disorder. But at the same time Peek had such an amazing ability to remember facts that he was dubbed "Kimputer". Apparently he had memorized the entire contents of thousands of books.
"You could ask Kim Peek thousands of questions," Draaisma says. "But if you'd asked him the price of a car, or a loaf of bread, he was liable to give you all kinds of crazy answers." Draaisma personally studied a man named Tom, who could simultaneously play 26 checker matches in his head, with moves transmitted via the telephone. "But if he went shopping, he needed a list – even if it contained only a few items."
The case of Jill Price
A few cases of extreme autobiographical memory are known, in which individuals preserve amazingly accurate memories of their own lives. In 2006 Jill Price made headlines as "The woman who can't forget." Price came to attention a few years earlier through a letter to psychologist James McGaugh. In it she claimed to be able to remember every day of her life since she was eleven years old.
McGaugh and his colleagues were initially skeptical and tested Price by giving her single dates. Oct. 3, 1987? "That was a Saturday. I spent the whole day in the apartment, with a sling on my arm, because I had injured my elbow." July 1, 1986? "I can see it all – the day, the month, the sommer. Tuesday." Price could name the friend she went with to a restaurant on that day. In ten minutes she listed how she had spent every Easter from 1980 to 2003. The scientists eventually concluded that Price could really remember every day of her life in precise detail. In 2006 they published a report on their investigations in the journal "Neurocase".
But Price doesn't represent a miracle of perfect memory, either. Neuropsychologist Gary Marcus accompanied her for two days, during which he submitted her to a number of tests. In one instance he asked her to study a list of words including the terms "thread", "eye", "sew", "thimble", "thorn" and "injection". It didn't contain the word "needle" – although most people given the test claim to have seen it. Price made the same mistake. Evidently her brain wasn't simply "photographing" the list.
The burden of memory
Marcus has an explanation for Price's ability: She spends every moment of her life thinking about her past. She has written a diary with 50,000 pages, has saved every stuffed animal she ever possessed and regrets that no one followed her around during her childhood with a microphone to record everything. The fact that she spends so much time remembering her past reinforces the memory with each incident of recall.
A parallel is the way a person's biceps grow if he or she visits the fitness studio five times a week – Price has "pumped up" her autobiographical memory through constant recall. Marcus actually believes that she suffers from a compulsive disorder. In her letter to McGaugh, Price recounted: "Most people say this is a gift, but to me it's a burden. Every day I replay my entire life in my head, and it makes me crazy!"
The ability to forget has advantages
There is a good reason that we normally forget a lot of the information that we once learned. Anything that seems unimportant, has no emotional meaning or is not recalled for a long period of time eventually fades from our brain. This is the only way to maintain a focus on information that is currently relevant and quickly respond to the environment.
The key task of memory is to take advantage of the past to learn for the future. Here an exact recording of the total complexity of all past experience would be a hinderance. Instead the brain attempts to generalize from a core of information. The framework in which events occur is often irrelevant and will be forgotten. This means, for instance, that most people know that Paris is the capital of France, but few remember exactly when they learned this fact. "It would be horrible, if everything we knew were accompanied by a memory that we connect to it," Draaisma says. "All of these associations would regularly overload our brains."
A defect in forgetting can lead to massive problems: many people with isolated gifts of memory are not capable of mastering the daily tasks of life. Memory master Shereshevsky had difficulties understanding abstract concepts and following stories as they were being read aloud, because he could not ignore unimportant aspects of the context.
The fictional character Funes suffers from quite similar problems: "He not only had difficulty understanding the general concept of a 'dog', which incorporates so many sizes and shapes; he was also disturbed by the fact that the dog at 3:14 (seen in profile) had the same name as the dog at 3:15 (seen from the front)." To create the concept of a "dog", a person needs to do more than simply record memories of multiple dogs. It's just as important to forget unimportant details to create a whole concept. "There is a thin line between remembering and forgetting," Draaisma says. "And to be unable to forget is not a wonderful thing."
Unter „Emotionen“ verstehen Neurowissenschaftler psychische Prozesse, die durch äußere Reize ausgelöst werden und eine Handlungsbereitschaft zur Folge haben. Emotionen entstehen im limbischen System, einem stammesgeschichtlich alten Teil des Gehirns. Der Psychologe Paul Ekman hat sechs kulturübergreifende Basisemotionen definiert, die sich in charakteristischen Gesichtsausdrücken widerspiegeln: Freude, Ärger, Angst, Überraschung, Trauer und Ekel.
- Borges, J. L: Das unerbittliche Gedächtnis. In: Fiktionen. Erzählungen 1939 – 1944. Fischer-Verlag, 2004.
- Shafy, S.: Endlosschleife im Kopf. Porträt der Amerikanerin Jill Price. Der Spiegel, Nr. 47 vom 17. November 2008 (zum Text).
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