Does training your brain boost memory and slow down the ageing process? It's all in the mind

But there is no evidence that brain training regimes will delay the development of Alzheimer's disease or other forms of dementia in elderly people, researchers said yesterday.

Such exercises, which have been made popular by games such as Nintendo's Brain Training, may even be damaging by reducing the amount of time older people spend on other activities such as exercise, the researchers said.

Adverts featuring stars including Star Trek actor Patrick Stewart and Hollywood star Nicole Kidman have helped make brain training trendy, with sales of the DS consoles soaring alongside games such as Dr Kawashima's Brain Training.

The new study, published in Alzheimer's & Dementia, did not look at the Nintendo brain training series, but focused on so-called "cognitive training" regimes which had been the subject of scientific trials.

Some of these products go further than simply saying they can improve memory, and claim to be weapons in the fight against Alzheimer's disease.

Researchers from American health organisation Lifespan set out to assess the effectiveness of cognitive training products, which have become a multi-million-pound industry in recent years.

Lead researcher Peter Snyder and colleagues looked at all trials conducted on these products in elderly people published since 1992, finding a total of ten studies. The researchers described the studies as "limited" and lacking in follow-up information on the participants.

They concluded "there was no evidence indicating that structured cognitive intervention programmes had an impact on the progression of dementia in the healthy elderly population".

Dr Snyder also expressed concern that money spent on these products could mean less is spent on healthier pursuits such as exercise.

The researchers called for more clinical trials to assess the impact of cognitive training.

Lindsay Scott, from Help the Aged Scotland, said: "I know that many older people enjoy doing puzzles such as Sudoku and crosswords as well as playing chess. Those who use computers also enjoy games such as solitaire.

"There is good evidence that keeping yourself engaged and the brain operational is just as important in maintaining good support networks as you get older. Not all pensioners have a large amount of money ... so we would not want them to rush out to spend money on something which maybe has a dubious evidence base.

"But buying a paper and doing a crossword or getting a book of puzzles from the library is inexpensive and will also help keep the brain active."

A spokesman for Nintendo said the games in "Brain Training" and "More Brain Training" were inspired by exercises developed by neurologist Dr Kawashima, "who believes the brain needs to be exercised to help stay fit in the same way our bodies need exercise to stay in shape".

He added: "Nintendo does not make any claims that 'Brain Training' is scientifically proven to improve cognitive function."