Everyone becomes a little more forgetful as they get older, but men's minds decline more than women's, according to the results of a worldwide survey.
Certain differences seem to be inherent in male and female brains: Men are better at maintaining and manipulating mental images (useful in mathematical reasoning and spatial skills), while women tend to excel at retrieving information from their brain's files (helpful with language skills and remembering the locations of objects).
Many studies have looked for a connection between gender and the amount of mental decline people experience as they age, but the results have been mixed.
Some studies found more age-related decline in men than in women, while others saw the reverse or even no relationship at all between sex and mental decline. Those results could be biased because the studies involved older people, and women live longer than men: The men tested are the survivors, "so they're the ones that may not have shown such cognitive decline," said study team leader Elizabeth Maylor of the University of Warwick in England.
The new study used data from the BBC Sex ID Internet Survey, conducted between February and May 2005. The survey had more than 250,000 respondents worldwide.
Survey participants completed four tasks that tested sex-related cognitive skills: matching an object to its rotated form, matching lines shown from the same angle, typing as many words in a particular category as possible in the given time (e.g. "object usually colored grey") and recalling the location of objects in a line drawing. The first two were tasks at which men usually excel; the latter are typically dominated by women.
Within each age group studied, men and women performed better in their respective categories on average. And though performance declined with age for both genders, women showed significantly less decline than men overall. Women slowed down more in terms of their decline, but when comparing men and women of the same age, men showed a greater amount of decline.
Maylor cautions that the skills tested have little practical use and that other factors such as social involvement and mental and physical exercise have more impact on cognitive decline. So while the trend might hold, there would definitely be a lot of variation man by man and woman by woman.
"You can't sort of say, 'Oh, you're a man, so you're going to decline faster than me because I'm a woman,'" Maylor said.