Most of us have probably been told at some point in our lives that women are better multitaskers. It seems obvious that the average working mother would have to do a lot of juggling: helping with homework, cooking dinner, talking on the phone, all after a long, demanding day at work. But just how good are the different genders at actually successfully completing multiple tasks, without messing anything up?

New research just out of Sweden indicates that there is not a shred of evidence to back up the stereotype about amazing female multitaskers. In fact, according to research by Timo Mantyla from Stockholm University, which will be published in an upcoming issue of Psychological Science, men are actually better at multitasking than women are.

Mantyla theorizes that successful multitasking is based on two different cognitive functions. One, executive function, is the ability to remember and update goals. The other is spatial function. While that may seem surprising, multitasking - remembering how long it takes lasagna to cook while scrubbing a bathtub - is often dependent on organizing to-do items in the "time of space". Men are considered to be better at spatial reasoning than women are, so Mantyla believes that differences in that arena, not executive function, would explain any gender differences.

Mantyla recruited an equal number of men and women, aged 19 to 40 years old, as volunteers for his challenge. Participants were tasked with monitoring three digital counters on a screen. They were asked to press a bar when the last two digits of a number shown on the first counter were 11, 22, 33, and so forth; when the last two digits of the number on the second counter were 20, 40, 60, and so on; and when the last two digits of the number depicted on the third counter were 25, 50, 75, and so on. The counters were not visible at the same time; participants needed to press a button in order to see one of the counters.

At the same time, participants needed to perform a "name-back test". Names would appear on the screen and the volunteers needed to identify if it was the same name as one that they had seen four names earlier.

Later, all participants took an executive control test. Mantyla theorized that those who had performed well on the executive control would also do well on the multitasking test. He was right on that count. Men also performed better than women on the multitasking test, making about 10 percent fewer errors.

Since executive control did not fully explain the increased ability for multitasking, Mantyla performed the same experiment with two variations. Participants needed to also complete a spatial reasoning test. Women also were required to record exactly where they were in their menstrual cycle.

Overall, men were better multitaskers in the second experiment. But the differences faded away depending on where women were in their menstrual cycle. If women were in their luteal phase, typically days 14 through 28, men were far superior. But if women were menstruating, they made up the difference.