Foer, like most memory athletes, taught himself to remember information through a process known as “elaborative encoding”—relating disconnected numbers, words, or facts to networks of existing memories and knowledge. “As bad as we are at remembering people’s names, as bad as we are at remembering phone numbers, as bad as we are at remembering step-by-step instructions from our spouses, we have amazing visual and spatial memories,” Foer said. Memory athletes’ skills come from turning the first, less memorable kind of information into the second kind.
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For example, to remember the names that go with an array of strangers’ faces, Foer creates mnemonic devices and visualizes them: A heavily bearded man named Mike is given a beard of mics; a crooked-nosed man named Bill is fitted with a duck bill. (“It helps to be a bit of a judgmental schmuck when you’re meeting people,” Foer said, “when you want to remember their names.”)
To memorize a string of numbers, he said, he assigns each digit from 1 to 9 a specific sound and strings the sounds together to create words (52 becomes a lion, 92 a pen) and then combines the words to form a memorable image (5292 is a writing lion). And to remember a shopping list, he places items in a “memory palace,” picturing himself pouring a gallon of milk over his head just outside his front door, then walking inside to see a chicken juggling some eggs. Memory athletes, he said, are always on the hunt for spaces they can turn into new memory palaces, “walking around, looking at buildings as structures to hold future memories.”
After studying accomplished memory athletes and “naive” controls who underwent memory training for six weeks, researchers found in 2017 that learning to employ mnemonic devices reorganized the connections in subjects’ brains. Their results confirmed memory champions’ insistence that their skills are learned rather than innate. And in 2002, fMRI evidence showed that when champions were in the process of memorizing or recalling something, their brains’ location centers lit up. The memory athletes were, as Foer described them, walking through their memory palaces and connecting unrelated information with physical spaces.
The sport of competitive memory is, Foer said, “an arms race,” with athletes constantly developing new tricks and shortcuts that give them an advantage over their competitors and allow them to set new records. Foer’s mentor, the memory athlete Ed Cooke, invented a system that paired every number from zero to 1 billion with a particular image. But the basic techniques they employ are, for the most part, very old, and were once much more commonly practiced. Poets and orators employed memory palaces millennia ago in ancient Greece; medieval scholars used them to memorize whole books. The strategy Foer demonstrated for remembering sequences of numbers, he notes, dates back to the 17th century.