This fascinating New York Times piece profiles the Extreme Memory Tournament (XMT):

The competitors gathered here for the XMT are not just anyone, however. This is the all-world team, an elite club of laser-smart types who take a nerdy interest in stockpiling facts and pushing themselves hard.

In his doctoral study of 30 world-class performers (most from Germany, which has by far the highest concentration because there are more competitions), Mr. Konrad has found as much. The average I.Q.: 130. Average study time: 1,000 to 2,000 hours and counting. The top competitors all use some variation of the memory-palace system and test, retest and tweak it.

This concept of how these people invoke a “memory palace” is very interesting:

Each competitor has his or her own variation. “When I see the eight of diamonds and the queen of spades, I picture a toilet, and my friend Guy Plowman,” said Ben Pridmore, 37, an accountant in Derby, England, and a former champion. “Then I put those pictures on High Street in Cambridge, which is a street I know very well.”

As these images accumulate during memorization, they tell an increasingly bizarre but memorable story. “I often use movie scenes as locations,” said James Paterson, 32, a high school psychology teacher in Ascot, near London, who competes in world events. “In the movie ‘Gladiator,’ which I use, there’s a scene where Russell Crowe is in a field, passing soldiers, inspecting weapons.”

More here.