By NEIL SEARS -Last updated at 00:52am on 7th January 2008
They say you can't teach an old dog new tricks - but whoever came up with that particular adage was probably young and foolish.
For contrary to the long-held assumption that brain power peaks between the ages of 18 and 26, new research indicates that it actually increases with age.
The ground-breaking report suggests that many preconceptions about ageing made by employers and policymakers need to be brushed aside.
The study - by psychologist Lars Larsen, of Denmark's University of Aarhus - looked at 4,300 U.S. servicemen who had undergone intelligence tests when they signed up aged around 20, and again 20 years later.
Comparing the two sets of results showed that mathematical skills among the servicemen - all Vietnam veterans - appeared to remain unchanged, rather than reducing with age, while their verbal skills actually improved considerably.