Now, a team led by Allan Reiss, MD, a Stanford professor of psychiatry and behavioral sciences and of radiology, has gained insight using a technique called hyperscanning. As explained in a press release:
Hyperscanning involves simultaneously recording the activity in two people's brains while they interact. And instead of using an MRI that requires participants to lie perfectly still and flat, the scientists used near-infrared spectroscopy, or NIRS, in which probes are attached to a person's head to record brain function, allowing them to sit upright and interact more naturally.
The 222 participants in the study were each assigned a partner. Pairs consisted of two males, two females or a male and a female. Then, while wearing the NIRS probes, each person sat in front a computer, across the table from their partner. Partners could see each other, but were instructed not to talk. Instead, they were asked to press a button when a circle on the computer screen changed color. The goal: to press the button simultaneously with their partner. After each try, the pair were told who had pressed the button sooner and how much sooner. They had 40 tries to get their timing as close as possible.
The researchers found that participants in male-male pairs and female-female pairs showed brain activity similar to their partners. Yet the male-female pairs performed just as well, even though their brain activity was different.
"It's not that either males or females are better at cooperating or can't cooperate with each other," Reiss said. "Rather, there's just a difference in how they're cooperating."
The study, which appears today in Scientific Reports, has several limitations, the authors say. It doesn't examine the entire brain and it only focuses on one type of cooperative task. But this type of work has applications for some types of disorders, says lead author Joseph Baker, PhD, a postdoctoral research fellow in psychiatry. "There are people with disorders like autism who have problems with social cognition," he said. "We're absolutely hoping to learn enough information so that we might be able to design more effective therapies for them."