Bats feeding on tree flowers

In sync

April 14, 2020
This article appeared in Berkeley Engineer magazine, Spring 2020

Humans aren’t the only species capable of getting on the same wavelength with each other. Research from Berkeley scientists shows that bats have synchronized brain activity when engaging in social behaviors, such as grooming, fighting or sniffing each other. Led by Michael Yartsev, assistant professor of bioengineering and of neurobiology, the study is the first to show neural correlation during social interactions by a non-human species.

In the study, Yartsev and postdoctoral scholar Wujie Zhang used wireless neural recording devices to measure the brain activity of bats interacting in a chamber. These devices captured signals that included the bats’ higher frequency brain waves, as well as electrical activity from individual neurons. The researchers found surprisingly strong correlations between the bats’ brains, especially for brain waves in the high frequency band. These correlations were present whenever the bats shared a social environment and increased before and during their social interactions.

To better understand these correlations, a team of undergraduate students went through hours of high-speed video of the bats, characterizing behavior in each frame. The lead researchers then analyzed the relationship between bat behavior and inter-brain correlation, allowing them to rule out other possible explanations for the synced-up brain activity, such as that the bats’ brains were simply reacting to the same environment, or that the bats were engaging in the same behavior. The researchers hope this work will help future studies on how brains process social interactions.