According to some french researchers:

……….Professor Lieury said that helping one’s children with their homework, reading, playing Scrabble or Su Doku or watching documentaries instead of soap operas matched or beat the console. The study tested Nintendo’s claims on 67 ten-year-olds. “That’s the age where you have the best chance of improvement,” Professor Lieury said. “If it doesn’t work on children, it won’t work on adults.”

The children were split into four groups. The first two did a seven-week memory course on a Nintendo DS, the third did puzzles with pencils and paper, and the fourth just went to school as normal.

Before and after the programmes, the children were set a variety of tasks – logic tests, memorising words on a map, doing sums and interpreting symbols. Researchers found that children using the Nintendo DS system failed to show any significant improvement in memory tests. They did do 19 per cent better in mathematics – but so did the pencil-and-paper group, while the fourth group did 18 per cent better. When it came to memorising, the pencil-and-paper group recorded a 33 per cent improvement, while the Nintendo children were 17 per cent worse. In logic tests the Nintendo children registered a 10 per cent improvement, as did the pencil-and-paper group. The children who had no specific training improved 20 per cent……….

You can read the full article HERE