Scientists at Johns Hopkins University have successfully recorded the brain activity of free flying bats.
The breakthrough, detailed in the journal eLife, could help scientists study the brains of animals as they behave naturally -- untethered and free of cumbersome equipment.
"If you want to understand how the brain operates in the real world, you have to have the animal moving through the world in a natural way," Melville Wohlgemuth, a postdoctoral fellow at Johns Hopkins, said in a news release. "This idea of recording the brain without wires is brand new. And no one has used it to understand how an animal senses the world and reacts to that information."
Until now, scientists have only been able to study the brain activity of animals as they perform basic -- and often contrived -- tasks and maneuvers.
To develop the light-weight device needed to record brain activity wirelessly, while still allowing the bat to fly and function normally, Johns Hopkins researchers teamed up with an outside engineering firm. Researchers used the device to study how bats interact with their surroundings as they fly.
The scientists combined brain activity readings with an echo model that predicts what the bat is paying attention to based on the high frequency sounds it bounces off of surrounding objects. By comparing the neural activity patterns with the patterns of the bat's high frequency squeaks, researchers identified brain cells essential to the mammal's ability to interpret and navigate three-dimensional space.
"We can see how the moving animal interacts with objects, just like a person would walking in the woods," Wohlgemuth said.
Scientists expect their breakthrough to open a range of new research opportunities.
"To see signals in the brain when an animal is really looking at something and then to see a neuron fire, was the holy grail for me," said grad student Ninad Kothari. "As this research goes forward, we can take the information we get from animals like bats, mice and owls and put it into human terms to potentially help people with attention deficits."
