Argh, it's on the tip of my tongue! Contestants in the Names and Faces competition focus at last year's World Memory Championships held in Guangzhou, China. A new field of mental athletes is currently vying for the 2012 championship.
In the gymnasium of a South London technical school, site of this year's World Memory Championships, Norwegian Ola Kaere Risa checks his stopwatch.
Risa is Norway's only contestant this year.
"I hope to defend the glory of my country," he says, laughing.
The 21st World Memory Championships are under way in London this weekend. About 75 competitors from some two dozen countries are vying to see who can memorize the most numbers, faces, playing cards or random words in a set amount of time.