You’re asked a math question you must solve entirely in your head. The answer is 2,396,232,838,850,303. What chance have you got of getting it right?

Alexis Lemaire with one of his little problems

Correct answer : zero.

Not, however, if you are Alexis Lemaire. He has broken the record for finding the 13th root of a 200-digit number. Basically, that looks like this :

85,877,066,894,718,045,602,549,144,850,158,599,
202,771,247,748,960,878,023,151,390,314,284,284,
465,842,798,373,290,242,826,571,823,153,045,030,
300,932,591,615,405,929,429,773,640,895,967,991,
430,381,763,526,613,357,308,674,592,650,724,521,
841,103,664,923,661,204,223.

Last December, at Oxford’s Museum of the History of Science Alexis broke his own record, reducing it to 77.99 seconds. Even with a calculator you wouldn’t beat Lemaire doing the calculation in his head.

How does he do it? “It is quite difficult. I did a lot of preparation for this. More than four years of work and a lot of training every day. A lot of memorizing. I need three things — calculating, memorizing and the third on mathematical skills. It is a lot of work and maybe a natural gift.”

One of the theories being put forward by researchers is that damage to one area of the brain creates compensation in another. Brain scientist Dr Allan Snyder has suggested that everyone may possess such abilities but be unable to access them.

The genius himself explains that what he does is to transform raw numbers into other structures so he can “see” the answer to the problem. “When I think of numbers sometimes I see a movie, sometimes sentences. I can translate the numbers into words. This is very important for me. The art is to convert memory chunks into some kind of structure.

“I see images, phrases, actions. It’s very tactile, sensitive. I have these associations between places and numbers. Some places are imaginary, I try to vary so I don’t confuse the numbers. It’s important to memorize. I have to be precise.”

Lemaire’s explanation is similar to that of British genius Daniel Tammet, who set the world record for reciting pi to more than 22,000 digits at the same museum in 2004. To him, he said, each number has a distinct colour and appearance, some beautiful, some not, with each complex calculation making up a landscape.

Now you know.

For some people with disturbed and disrupted sleep patterns who have also suffered a mild traumatic brain injury, the trouble could be a circadian rhythm sleep disorder and not insomnia. According to the Academy of Neurology, sleep disorders can be caused by mild head injuries.

Researchers studied 42 individuals who reported insomnia following a mild traumatic brain injury. After undergoing scans, sleep studies and measurements of temperature and saliva melatonin, the study found that 36% of these patients had a circadian rhythm sleep disorder (CRSD).

Patients coming to sleep clinics due to insomnia have a CRSD rate of only 7 to 10 percent. The findings of the study indicate that misdiagnosis of CRSDs could lead to it being labeled as insomnia and the prescription of sleep medications which do nothing to normalize sleep-wake cycles. Additionally, circadian rhythm sleep disorders may be accompanied by other associated psychological and cognition problems.

The study is published in the April 3 issue of Neurology

The Academy of Neurology