Followers

Tuesday, July 22, 2008

Genes could explain memory differences between men and women

By Richard Gray, Science Correspondent

When it comes to memory it is clear that men and women are simply not on the same wavelength.

While men may fail to match a woman's ability to remember the date of an anniversary, they are better at storing a seemingly endless cache of facts and figures.

Scientists believe they have now uncovered the reason for this difference between the sexes – they make the memories in different ways.

Researchers at the Institute of Psychiatry, King's College London, have found that males use different genes from females when making the new connections in the brain that are needed to create long-term memories. They believe this might explain why men are far better at remembering "tactical" memories, such as travel directions and trivia, while women form more "emotional" memories such as birthdays, wedding anniversaries and details about the world around them.

Professor Peter Giese, who led the Medical Research Council- funded research , said they had identified two genes that seemed to be important for learning and making memories in males but not females.

He said: "It is unexpected that there should be such a difference within a species, but then we have to remember that males and females are far from identical at the genetic level as males have an X and Y chromosome while females have two X chromosomes.

It is conceivable that the differences we found do account for the differences in the way the memories of men and women perform in different circumstances."

The researchers used mice to study the role that certain genes play in how long term memories are made in males and females. Using a series of tests such as a maze they were able to show that male mice were faster at making the spatial memories that allowed them to learn a route out of the maze.

Professor Giese and his team then bred mice that lacked two key genes and found that the males were no longer able to learn the route out of a maze. The females, however, were unaffected by the loss of these genes. He said: "We see these sex differences in humans too as males and females use different strategies when it comes to remembering a route through a city, for example. In some tasks males are better than females and in other occasions females are better than males.

"These genetic differences could be very important in studying diseases like Alzheimer's, where memory is affected. Females are affected by Alzheimer's more than males, so it could mean the way females make memories is more vulnerable to disease."

His findings follow research elsewhere that is revealing just how different the brain's of men and women really are.

One study at Harvard Medical School found that parts of the frontal lobe, which houses the decision-making and problem-solving functions, are larger in women compared to men. The limbic cortex, which regulates emotions, is also larger in women.

The Parietal cortex, which is involved in space perception and balance, is bigger in men. Professor Carey Cooper, a psychologist who specialises in sex differences at Lancaster University, said: "It is probably a combination of the genetics and hard wiring of the brain together with the social imprinting of gender that has led to the behavioural differences we now see between men and women."

Original here

No comments: