Bombarded with adverts promising a longer, healthier life, Peter Bowes in Los Angeles goes in search of eternal youth.

Is mental infirmity an inevitable consequence of getting old? Or could we enjoy a more clear-headed old age?

In California it's common to see advertisements promoting brain training or brain workouts which claim to help reverse the effects of ageing.

"The old adage is really true: if you don't use it, you l ... Read more »