Fifty finalists from 16 nations are due to battle for the title of 2005 World Memory Champion.
In one event finalists must memorise a poem in 15 minutes
Over three days the participants will compete in 10 disciplines, including memorising numbers and packs of cards.
The championship is being held at Oxford University's Examination School, where a winner is set to be declared by Monday evening.
Britain's best hope is Derby-born Ben Pridmore, 28, the reigning world champion, or Grand Master.
Mr Pridmore currently holds several records including memorising a pack of cards in 32.13 seconds.
It is believed his stiffest challenge will be from the German national champion, psychologist Dr Gunther Karsten, currently ranked five in the world.
Organiser Andrew Hughes-Hallett said: "This year the heat of the competition will revolve around the challenge from the German contingent.
"Dr Karsten has been doing some intense training and feels pretty good about himself."
Preparation for the competition - also known as the Memoriad - is intense.
Competitors will have ensured they are at maximum fitness levels to ensure a good flow of oxygen to the brain which enhances performance.
For each event they will also have developed their own technique and strategy. One such technique is to use images of people to represent playing cards.
The contest will run from 0930 BST Saturday until Monday evening, when individual points accrued in each event will be added up and a winner declared.