For Indian Whiz, Incredible Recall Is as Easy as Pi

After spending a good deal of time with Rajan Mahadevan--after he had recited, from memory, the first 30 digits of Euler’s constant, after he had written, in his rapid-fire left-handed chicken scratch, a block of 50 random digits he had last seen at 9:15 a.m. on Oct. 5, 1987, after he recited the row and seat number he was assigned on Air India’s Flight 107 from Madras to Bombay nine years ago, after he had spun off the reservation phone numbers for Braniff, United, TWA, Delta, Southwest, American and Continental airlines, after he had laughed about the trouble he has remembering the 31,812th digit of pi--after all that, he said he wanted to chat again and asked for a telephone number.

But when offered a business card, a look of consternation creased Mahadevan’s face. “No--I’m sorry! I’m sorry!” he told a visitor with alarm. “To use one of your cards for me, there is no need. Just tell me.”

Just tell him! Of course! Here’s a living natural phenomenon, a research psychologist’s dream come true, one of the more prodigious numerical memorists in the history of recorded science, surely he could remember a telephone number.

Told the digits, Mahadevan listened intently, then closed his eyes for a few seconds and fell into deepest thought, rocking to and fro on his chair. When he opened his eyes and came back into the world, he flashed his big, friendly grin and recited the number, backward, then forward.

“It’s an easy number to remember,” he said cheerfully. “First place, only 10 digits. Second, (it contains) the series 623, which is reminding me of Avogadro’s number, you know, the atomic-weight constant.

“I will never forget.”

Formidable Possibilities

Somehow, that commonplace promise seemed to carry formidable possibilities when uttered by Rajan Srinivasen Mahadevan.

Ambling around the Kansas State University campus in a T-shirt, old painter pants and sandals, Mahadevan looks every bit the classic grad student. He lives in a hopelessly cluttered bachelor apartment and spends his evenings at the campus hangout, a bar and pool parlor called Fast Eddie’s.

But the loquacious 32-year-old from Mangalore, India, is also one of the world’s half-dozen or so living hypermnesiacs--people with gargantuan memory powers. A student of psychology, he has such a stupendous memory for numbers that he himself has become a research tool for psychologists.

He is the subject of a $157,000 National Institute for Mental Health study aimed at a question that scientists have pondered since time immemorial: How does our memory work?

Among psychologists and neurobiologists--not to mention engineers, who are trying to replicate human mental processes in computer circuits--the machinery of memory is a hot topic of research and hypothesis.

Theories abound, but so far it is still an abiding mystery how something as ephemeral as a fragrance, a feeling, a face, a formula or a trivial fact can lodge somewhere in the mind and stay there forever, available for retrieval minutes or months or years or decades later.

Researchers are trying to determine whether the memory apparatus is a single large network, or whether people have different memories with different capabilities.

Mahadevan, for example, is prodigious with numbers. But he seems to be worse than average at recalling faces; he can never remember where he put his keys.

Retrieving Data

Another burning question in the psychology labs is why some data pop out of the memory banks instantaneously while others take a while. When you hear the phrase I can’t get no ... you may have immediate and effortless recall of the rest of the lyric, the melody, the band and the person you were dancing with the first time you heard the song.

But if asked, “What color was the door you used most often to enter the house you lived in two houses ago?”--a common question in memory experiments--it likely would take moments of hard mental exercise to trace back through the neural network and extract the answer.

Some researchers pursue inquiries with tests on normal people. Others want to work with certified monster memories--with truly rare birds like Mahadevan, the subject of study on three continents since his first trip to the United States in July, 1980.

“I went to Chicago,” he recalls, “and stayed in Room 109 of the Conrad Hilton. Ho-no! I’m sorry! I’m sorry! It was Room 1409. The bill was $109. I attended the International Congress on Yoga and Meditation, and there I recited the first 10,000 digits of pi.”

The Greek letter pi is the mathematician’s symbol for the ratio between the diameter and the circumference of a circle. Most people know its value as 3.14, or perhaps 3.14159. But, in fact, its decimal expansion runs on and on forever; there is no known pattern or duplication in the endless string.

For that reason, and because the ratio is too difficult to compute on your feet, reciting pi is a favorite test of numerical memory.

Mahadevan’s assault on pi reflects a recurring quest of his life--the effort to find some practical use, some path to money or fame or accomplishment, in his amazing gift.

“My friends are saying always to me, ‘Rajan, how can you use this memory?’ And I respond, ‘Tell me! I’m looking! Tell me how I can make money, and I will do it.’ ”

The son of a prominent surgeon in Mangalore, Mahadevan as a boy astounded friends by reciting, say, the score of the cricket test match on March 15, 1877, or the complete railway timetable for Calcutta Station. But there was not much to be gained from that kind of display.

Eventually he wrote the editors of the Guinness Book of World Records in London about his talent; they suggested he focus on pi.

Mahadevan found a book-size listing of the constant and went to work. By mid-1980, when he first came to America, he had memorized 10,000 digits.

On July 4, 1981, he stood before a packed meeting hall in Mangalore and started reciting pi from memory. He raced through the first 100 digits so fast the official observers could hardly keep up. He cruised easily past the famous segment, 762 digits along, where six 9s in a row occur.

After 10,000 digits, he paused for a Pepsi. He paused again at 20,000 digits, and again at 25,000. In all, he recited numbers for 3 hours 49 minutes. He remembered 31,811 digits of pi without a single error.

Why did he stop there? “I just forgot,” Mahadevan explains with a shrug. “The 31,812th digit, I don’t know why, I am always stumbling over that one.”

In any case, 31,811 was enough to earn him a place in the Guinness book. “People ask me, ‘Rajan, why would you want to know 30,000 or 50,000 digits of pi?’ he says. “Well, it is the challenge, to meet a challenge. And because the Guinness regulations are such that you have to do this to get in the book.”

‘Ballyhoo’ Started

The psychological community’s interest increased after Mahadevan made Guinness. “That’s when the ballyhoo really started,” he says. “And all the tests. That’s what’s the reason for this big government grant. . . .”

To help answer how he does what he does, Mahadevan gave a demonstration of his memory power. “Why don’t you write a 6-by-6 matrix of digits, random digits, on the blackboard?” he said.

This done, he stared at the 36 numbers. After two minutes, the numbers were copied, then erased. The memory whiz still stood there with face crinkled in deepest thought. He cradled his chin in his hand and rocked back and forth rhythmically from one sandal to the next.

Eventually, he started reciting the numbers, row by row, in his clipped, quick Indian accent: 1, 1, 1, 4, 6, 7; 7, 8, 3, 1, 2, 4; 1, 8, 0, 2, 7, 9; 6, 1, 7, 4, 5, 3; 3, 9, 1, 6, 5, 5; 3, 2, 6, 7, 8, 9.

He had the figures exactly. He had them right again when he recited all 36 numbers backward. He responded flawlessly when asked to recall diagonals and individual rows or columns within the square. Clearly he had committed the numbers to memory. But how?

He launched into an explanation that was as mysterious as the feat itself.

“I scan the entire thing and start to make associations,” he said. “For example, there is ‘111’; that’s called a ‘Nelson’ because Adm. Nelson had one eye, one arm and one leg. I see a ‘312’ in there: area code of Chicago. There is ‘1802’, which I reduce to ‘plus 2’ because John Adams occupied the White House in 1800. The ‘1745’ I remember as 39, because Ben Franklin was 39 in 1745.

“I don’t know why I make those particular associations. These things come to me. They come to me naturally because I have an incredible knowledge base.”

With all the academic concentration on his gift, Mahadevan, too, became fascinated with memory. He dropped out of engineering school when he was 23 and switched to psychology. He earned a master’s degree in India at the University of Mysore, and began thinking about advanced work in the United States.

He applied to Kansas State University (“it was a financially accessible school,” with a good reputation in psychology, he says) and moved in 1987 to this campus town.

One scholar he quickly got to know was Prof. Charles Thompson, who has made memory his professional specialty and for years has run tests on volunteers. In a standard “digit span task” test, Thompson recites numbers, one per second, and asks volunteers to repeat all they can remember. The average person scores seven to 10. In a few cases, Thompson found people who can recall a random series of 16 or even 20 digits for a day or so.

Thompson had read and reread the honored study “The Mind of a Mnemonist” by the Russian A. R. Luria, one of the great psychologists of the 20th Century. In his charming volume, Luria relates that one day “a man came into my laboratory and asked me to test his memory.” This led Luria to decades of ground-breaking work with a subject known as “S.,” who never forgot anything he heard or read.

Nothing that earthshaking, of course, had ever happened to Thompson. Then, one day in September, 1987, a thin young graduate student from India walked into his office. “He said he wanted to work on memory studies,” Thompson recalls. “I asked him what area of memory he was interested in. He said, ‘Mine.’ ”

Within a month, Thompson and his colleagues had submitted a grant proposal to the National Institute of Mental Health for a three-year study of Mahadevan, who, for example, on the digit span test regularly repeated 50 digits and sometimes more.

The study is under way, meaning reports on the Mahadevan memory eventually will begin to appear in journals. Mahadevan will take his place in literature with memory giants of the past, about whom there are rich accounts.

John Milton reportedly knew by heart every line of Homer’s “Iliad” and “Odyssey” and Virgil’s “Aeneid,” not to mention every line ever written by John Milton.

Recite Any Line

That achievement was approached in modern times by Prof. Alexander Aitken, a British mathematician and classicist who invented the word hypermnesia. He could recite any line of Virgil if given the book and line number.

The most powerful--and, eventually, self-devouring--memory in academic literature belonged to the Russian journalist Shereshevskii, Luria’s “S.” His had the classic “iconic” memory--he turned every word or number he encountered into a striking image, which he never forgot.

S. remembered, verbatim, every conversation he ever had, a trait that got him in trouble at his newspaper when editors questioned why he never took notes. His memory for numbers seems to have been roughly as strong as Mahadevan’s, though his method was different.

He saw the number 1 as a tall, thin man. He saw 6 as a man with a swollen foot, 7 as a man with a mustache, 8 as a stout woman. Given the series 7186, he would create a mental image of a fat woman surrounded by three men; that image stayed with him for life.

S.’s story ended tragically. Gradually he became unable to distinguish current conversation from another he might have had 30 years earlier. His mind filled to overflowing and he ended his days in an asylum.

‘Healthy Phenomenon’

Rajan Mahadevan is too cheery, too upbeat, too optimistic to brood over S.’s fate. Such a thing could never happen to him. “Unlike S., I do forget. I think that forgetting is a very healthy phenomenon.”

He argues, perhaps a bit defensively, that “this memory thing is not my whole life. I have a life here in Manhattan. My primary interest now is to get through here and get my Ph.D. I have a need for friends. I have a need to find a woman.”

At Fast Eddie’s, the campus hangout, regulars are teaching him to play pool, and in return he entertains. Almost nightly he is approached by students who rapidly spin off the serial numbers from four or five dollar bills and challenge him to repeat them. He is surprised at their awe when he succeeds. “Those numbers--only eight digits apiece,” he says.

The constant pi runs longer than eight digits, of course, but Mahadevan is still working on that number, too. In 1988, a Japanese memorist, Hideaki Tomoyori, recited 40,000 digits of pi from memory, displacing Mahadevan from the Guinness book.

Mahadevan is determined to get back the record. He thinks it will take 100,000 digits to win a secure place, so he is studying off and on toward that goal. The work is “rather pleasurable,” he says.