Mental calculator

Mental calculators are people with a prodigious ability in some area of mental calculation, such as multiplying large numbers or factoring large numbers.

Mental calculators were in great demand in research centers such as CERN before the advent of modern electronic calculators and computers. See, for instance, Steven B. Smith's 1983 book The Great Mental Calculators.

The world's best mental calculators are invited every two years to compete for the Mental Calculation World Cup. On September 25, 2016, 27-year old Yuki Kimura of Japan, succeeded 13-year-old Granth Thakkar of India, as the current world champion. (2016-2018). Yuki Kimura is the 2nd Japanese person to win the Cup, after Naofumi Ogasawara won it in 2012.

In 2005 a group of researchers led by Michael W. O'Boyle, an American psychologist previously working in Australia and now at Texas Tech University, has used MRI scanning of blood flow during mental operation in mathematical prodigies. These math prodigies have shown increases in blood flow to parts of the brain responsible for mathematical operations during a mental rotation task that are greater than the typical increases.

In Frank Herbert's novel Dune, specially trained mental calculators known as Mentats have replaced mechanical computers completely. Several important supporting characters in the novel, namely Piter De Vries and Thufir Hawat, are Mentats. Paul Atreides was originally trained as one without his knowledge. However, these Mentats do not specialize in mathematical calculations, but in total recall of many different kinds of data. For example, Thufir Hawat is able to recite various details of a mining operation, including the number of various pieces of equipment, the people to work them, the profits and costs involved, etc. In the novel he is never depicted as doing actual academic mathematical calculations. Mentats were valued for their capacity as humans to store data, because computers and "thinking machines" are outlawed.

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