With a few weeks of training, a group of ordinary people became as skilled at remembering information as competitive "memory athletes," who use symbols and associations to display seemingly superhuman powers of recall.
Memory athletes hold competitions where they are challenged to recall and repeat long strings of random numbers, facts, dates and other information. The skills they use date back to ancient Greece and Rome — possibly further — and were once so commonly used they have been considered vital to the development of the Western intellectual tradition.
Some mnemonics live on today — schoolchildren use acronyms and other devices to remember facts and dates, for example — but few people today show the exceptional skill with it that memory athletes do.
Despite their abilities, most memory athletes insist they have no innate exceptional ability to remember things.
A Stanford researcher named Boris Konrad is a memory athlete, and he and a group of other researchers conducted a series of experiments showing how training ordinary people in memory actually bulks up certain regions of the human brain and vastly improves their powers of recall.
The team published the study Wednesday in the journal Neuron.
In one experiment, the researchers gave a word memorization test to 17 memory athletes and a control group made up of untrained people. The athletes remembered nearly 71 of 72 words after a 20-minute timed memorization session. The control group members averaged only about 40 correctly recalled words under the same conditions.
Before doing this, the researchers took fMRI scans of all the memory athletes, while telling all of them to relax and let their minds wander. This gave the team an idea of what regions of the athletes' brains were most active during periods of rest.
The researchers then gathered a group of 51 untrained people with ordinary powers of recall, and split them into three groups.
They gave the first group a six-week course of daily online training sessions in the method of loci — a classic mnemonic method where a person ties the things that need to be remembered (such as a string of numbers) to physical locations the person is familiar with on a much-traveled route (such as a daily commute or a walk to the local library).
The person imagines traveling this route and mentally "places" these things in locations on the route.
The second group received six weeks of a different kind of training to improve working memory that did not involve the use of mnemonic techniques.
The third group got no training at all.
The differences among the groups were stark.
After six weeks, the group trained in the loci method recalled nearly all of the words in a word memorization test, just like the memory athletes. In contrast, neither the group that received the training in working memory, nor the control showed dramatic improvement.
In addition, the brains of people trained in the method of loci showed the same sorts of resting brain activity the memory athletes showed in fMRI scans. In fact, the researchers found that the changes seen in the brain scans were a reliable indicator of how well someone would perform on a test.
"This suggests that a six- or eight-minute snapshot of a person's functional connectivity has some value in predicting how they perform in the world," said in a news release.
These techniques will not give an ordinary person a flawless memory — memory athletes "lose their car keys as frequently as you and I do," said researcher William Shirer, in the release.
But those trying to remember something in particular could see dramatically improved results by employing a few old tricks.