The "soroban," Japan's traditional abacus, is drawing renewed interest as a tool to promote the development of children's mental capacities and to help fight dementia in the elderly.

At a soroban class in Tokyo's Nerima Ward, early elementary school children practice a mental calculation technique known as "anzan," or blind calculation. Students are taught to visualize a soroban in their heads to perform calculations with the help of a computer that prompts them with instructions and shows numbers and a scaled-down five-bead abacus on its screen.

"The soroban helps children improve not only their calculation ability but also their ability to concentrate and memorize because it requires them to use their eyes, ears and fingertips at the same time," said Kazuo Kayama, who teaches soroban classes.