People who spend money on "brain trainers" to keep their minds agile may get the same results by simply doing a crossword or surfing the internet, according to research published today.

A panel of experts, including eminent neuroscientists, found there was no scientific evidence to support a range of manufacturers' claims that the gadgets can help improve memory or stave off the risk of illnesses such as dementia.

Devices such as the Nintendo DS, endorsed by the actor Nicole Kidman and the singer Cheryl Cole, have enjoyed a surge of popularity recently. But the experts employed by the consumer group Which? concluded that much of the evidence supporting the claims was "weak" and that in some cases other activities, such as playing standard computer games, could have the same effect.

Importantly, none of the "brain training" claims were supported by peer-reviewed research published in a recognised scientific journal.

Which? asked a panel of scientific experts to examine gadgets and their claims. They included Dr Kawashima's Brain Training, Mindfit and Lumosity.

Martyn Hocking, editor of Which?, said: "If people enjoy using these games, then they should continue to do so - that's a no-brainer. But if people are under the illusion that these devices are scientifically proven to keep their minds in shape, they need to think again."

Which? members who had written to the organisation about brain training were asked to try the products for a month. One of the experts, Dr Adrian Owen, assistant director at the Medical Research Council's cognition and brain sciences unit in Cambridge, said of the research involving one group: "If they'd been asked to play Space Invaders for a month and improved at it - as surely they would - would we have concluded this was a beneficial form of brain training? Probably not."

Michael Scanlon, a neuroscientist from Lumosity, defended the company's research standards, and said: "We would never say Lumosity is proven to improve day-to-day living, but there is more and more evidence it does. We have actually conducted our own clinical trials to measure effectiveness of the product."

Also under the spotlight was Mindfit, a CD-Rom endorsed by the scientist Lady Greenfield. Two of the three studies it used to support its claims that it improved mental performance were found to be flawed. It also claimed that "cognitively challenging" activity protects against Alzheimer's. Bruce Robinson, chief executive of MindWeavers, which produces MindFit, said: "If you look at the wider evidence in the field the broad conclusion is that brain stimulation is working. With the MindFit product, a study was done by an independent medical centre in Israel which supported that evidence. We are not claiming MindFit will stop Alzheimer's."

Nintendo said: "Nintendo does not make any claims that Brain Training is scientifically proven to improve cognitive function. What we claim is the Brain Training series of games, like playing sudoku, are enjoyable and fun. These exercises can also help to keep the brain sharp."

Tried and tested

Dr Kawashima's Brain Training (Nintendo) £110 including DS console:

Instructions say it can help consolidate memory and creativity

Which? No evidence that using this product will have any functional impact on your life whatsoever

Mindfit (PC CD-ROM) £88

Company claims "exercises important abilities known to decline in later life"

Which? Tests didn't show using it was significantly better than playing Tetris

Lumosity (online training system) Luminos Labs, £4.99 a month

Company says: "Exercises ... designed to stimlulate neuroplasticity that leads to improved cognitive ability"

Which? Does not mean improvements on tasks will lead to improvements in day-to-day living