Women `age better'

The Times, London: Men's brains may be larger but women hold a trump card in the mental bat- tle of the sexes: their grey matter behaves as if it were three years younger.

Scientists measuring the brain activity of more than 200 people found that female brains were more youthful than those of males of the same age. The relative sprightliness was detectable even among the youngest subjects.

Manu Goyal, of the Washington University School of Medicine in St Louis, said the results could offer clues about why women tended to outperform men in cognitive tests in their seventies: "This could mean that the reason women don't experience as much cognitive decline in later years is because their brains are effectively younger." 

Previous studies have shown that women tend to beat men when it comes to verbal fluency and fine motor skills. Men tend to outperform women in spatial tasks. As they enter their eighties, the women's performance declines less rapidly.

Dr Goyals research used artificial intelligence to determine the "metabolic" age of brains by measuring their response to sugar. Children use a lot of sugar for brain development in a process called aerobic glycolysis.

In adolescents, a considerable portion of brain sugar remains devoted to the process. The fraction drops steadily with age, levelling out by the time people reach their sixties.

The study, in the Proceedings of the National Academy of Sciences, measured the proportion of sugar committed to aerobic glycolysis in brains ranging in age from 20 to 82. The scientists then used an algorithm to guess the ages of each of the subjects using data gathered from the other sex. In one experiment the algorithm gave brain ages for the women that were an average of 3.8 years younger than their true ages.