初夜会改变男人大脑结构

　　Losing your virginity really could be life-changing. Having sex apparently alters the structure of the brain – in men, at least.

　　A Japanese study of tiny spines that occur between brain cells revealed virgin male rats to have far more of them than more sexually experienced counterparts.

　　This implies the spines drive sex for the first time and then they shrink or disappear. It may one day be possible to create a pill for humans that increases the growth of spines. This could help boost libido, New Scientist reports.

　　Stuart Tobet, a neuroscientist in the US, said the studies provide a ‘glimpse into how changes in the structure of spines contribute to the ability to display sexual behaviours in rats and perhaps by extrapolation, to other mammals, including humans.’

　　Once their mission is achieved, the spines are no longer needed and so shrink or disappear.

　　What is more, the microscopic spines may also affect men’s early sexual encounters, this week’s New Scientist reports.

　　It was already known that several brain regions linked to sexual behaviour differ in size between the sexes in humans and other animals.

　　To find out whether an area known to be bigger in males was altered by having sex, the Saitama University researchers compared the brains of male rats who had never had sex before with their more experienced cage-mates.

　　They found that the number of brain spines was significantly lower in the non-virgins.

　　Researcher Shinji Tsukahara says the decrease in spines may have been caused by a number of factors, including hormonal changes triggered by the presence of a female.

　　He said that the spines may serve as a ‘one-way road to learn how to mate’ and once used they are no longer needed.