The Science of Memory: An Infinite Loop in the Brain
Jill Price can rattle off, without hesitation, what she saw and heard on almost any given date. She remembers many early childhood experiences and most of the days between the ages of 9 and 15. There are virtually no gaps in her memory.
She can also date s that were reported in the media, provided she heard about them at the time. When and where did the Concorde crash When was O.J. Simpson arrested When did the second Gulf War begin Price doesn’t even have to stop and think. She can effortlessly recite the dates, numbers and entire stories.
"People say to me: Oh, how fascinating, it must be a treat to have a perfect memory," she says. Her lips twist into a thin smile. "But it’s also agonizing."
In addition to good memories, every angry word, every mistake, every disappointment, every shock and every moment of pain goes unforgotten. Time heals no wounds for Price. "I don’t look back at the past with any distance. It’s more like experiencing everything over and over again, and those memories trigger exactly the same emotions in me. It’s like an endless, chaotic film that can completely overpower me. And there’s no stop button."
Can someone who cannot forget even fall in love Can they forgive, either others or themselves Price’s life has had its share of suffering, including family strife, her mother’s cancer and, later, the sudden death of her husband Jim. Because she was hounded by bad memories, grew depressed and feared that she was going crazy, she sat in front of her computer on June 5, 2000 and typed a single word into Google: memory.
That was how Price found James McGaugh, and became part of a scientific case study.
McGaugh is one of the leading experts on memory in the United States. He founded the Center for the Neurobiology of Learning and Memory at the University of California in Irvine.
"I was skeptical, of course, when Jill told me her story," says McGaugh, a slim, grey-haired man with glasses. "But I’ve spent most of my life studying the mechanisms in the brain that are associated with the development of lasting memories. So I thought that I should at least meet the woman."
McGaugh and his staff realized they were looking at an exotic case, perhaps even a scientific sensation. For that reason they took a thorough approach, and for five years they subjected Price to batteries of neuropsychological (神经心理学 ) tests, combed the professional literature for similar cases and developed special questionnaires to allow them to test her memory.
Once she was asked to write down the dates of all Easter holidays from 1980 to 2003. "It took her 10 minutes, and she only got one of the 24 dates wrong, where she was off by two days," says McGaugh. He had Price repeat the test two years later, and the second time she got all the dates right. "I thought that was especially impressive," says McGaugh, "because she is Jewish. Easter means nothing to her."
McGaugh and his colleagues concluded that Price’s episodic memory, her recollection of personal experiences and the emotions associated with them, is virtually perfect. A case like this has never been described in the history of memory research, according to McGaugh. He explains that Price differs substantially from other people with special powers of recall, such as autistic savants(自闭学者), because she uses no strategies to help her remember and even does a surprisingly poor job on some memory tests.
It’s difficult for her to memorize poems or series of numbers--which helps explain why she never stood out in school. Her semantic memory, the ability to remember facts not directly related to everyday life, is only average.
Two years ago, the scientists published their first conclusions in a professional journal without revealing the identity of their subject. Since then, more than 200 people have contacted McGaugh, all claiming to have an equally perfect episodic memory. Most of them were exposed as fakes. Three did appear to have similarly astonishing abilities. "Their personalities are very different. The others are not as anxious as Jill. But they achieve comparable results in the tests," McGaugh reports. The subjects do have certain compulsive traits in common, says McGaugh, especially compulsive hoarding.
In neurobiological terms, a memory is a stored pattern of links between nerve cells in the brain. It is created when synapses in a network of neurons are activated for a short time. The more often the memory is recalled afterwards, the more likely it is that permanent links develop between the nerve cells--and the pattern will be stored as a long-term memory. In theory there are so many possible links that an almost unlimited number of memories can be permanently stored.
So why don’t all people have the same powers of recollection as Jill Price "If we could remember everything equally well, the brain would be hopelessly overburdened and would operate more slowly," says McGaugh. He says forgetting is a necessary condition of having a viable memory--except in the case of Price and the other three memory superstars.
For McGaugh, there is another reason why people with such phenomenal memory are so puzzling. They challenge a theory on which his research has been based for the last half a century. This theory, based on clinical observation, says memories are stored in greater detail and with more staying power when they are tied to emotion.
Sensations are emotionally processed in the amygdala, a specific part of the brain’s limbic system. There decisions are made as to which information should remain in long-term memory. The more powerfully the amygdala is activated, the greater the likelihood of a permanent memory. "But now here we have these four people who seem to violate this principle, because they also remember the most b and inconsequential things," says McGaugh.
The Science of Memory: An Infinite Loop in the BrainWhen McGaugh first heard Price’s story, ______。