That's why women recover better after a stroke

Apr 14, 2007 10:43 GMT  ·  By

The minds of the two sexes are so differently fired: men want sex, women want money ...

The difference is present also when we are planning how to reach for something, according to a new research at Faculty of Health's School of Kinesiology, York University, made by associate professor Lauren Sergio and Dr. Diana Gorbet.

The researchers spotted differences in patterns of brain activity in men and women accomplishing visually-guided tasks like employing a computer mouse or driving a car. "We found that in females there were three major brain areas involved in visually-guided movement and they showed activity on both sides of the brain in most of the exercises in the study. In contrast, male brains lit up on both sides only for the most complex exercise", said Sergio.

The eye-hand coordination study investigated what the brain does when the visual system is dissociated from what the hand is effectuating. Each subject's brain activity was monitored by a fMRI machine while accomplishing increasingly-complex tasks.

The brain activity was checked just up to the moment when movement started, because any movement made in the fMRI machine would have impeded the achievement of a clear image of brain activity. "The differences between the sexes were so clear that Gorbet first noticed them while doing an earlier study that was not designed to separate out male and female results. In the type of eye-hand coordination research we do, we know there are differences between males and females when it comes to visual spatial processing - how you mentally rotate an object," said Sergio.

"But nobody has ever looked at action, at real-world relevant type of movement, which is what we're doing. We're studying eye-hand coordination when what the visual system is seeing is dissociated from what the hand is doing."

It was known that when you employ your right hand to effectuate an activity, the brain's left cortex increases its activity.

But the new research noticed that in females, both sides of the brain were excited during these eye-hand coordination investigations.

In men, this took place just when they were planning extremely complex tasks, like when the joystick was adjusted to move the cursor in the opposite direction to the one expected. "There's a lot of literature about how males and females differ in performance. But in all of these exercises, what they saw was exactly the same, what they did was exactly the same, so the difference occurred in the processing in between what they saw and what they did," said Sergio.

This discovery explains a different result of a stroke in men and women. "If the stroke is only on one side of the brain, a woman may have rehabilitation options that the man may have more trouble with, because the woman may be able to perform tasks using the other side of her brain, which is used to being fired up. We also need to recognize that men may have more trouble with rehabilitation, and may need to be checked more carefully before they resume everyday activities such as driving", said Sergio.