Israeli scientists have found that bats in mid-flight have an intricate 3D compass to aid navigation.
Human’s clearly have something similar to the navigational skills of the bat, but few are willing to have Israeli neuroscientists plant recorders in their brains to study this. But that is precisely what they did with a number of bats. Arseny Finkelstein, the neuroscientist at the Weizmann Institute of Science in Rehovot, Israel, who led the study, along with his colleagues placed recorders weighing only a few grams inside the bats’ brains. The recorders couldn’t weigh more or they would have interfered with the bats’ flight.
What they found was that bats have different brain cells to deal with up-down, left-right, and rotating motions. Syncing the data from the recorders with the direction of the bats’ heads in flight (using high-speed video cameras) they were able to map this 3D compass in flight.
Bats: Different cells for different directions
“This is the first study that’s shown any neural correlate to 3D navigation,” says Finkelstein. “What we found is that there are basically three types of brain cells—albeit with some overlap—that are sensitive to each one of these dimensions.”
Scientists have long known, through a series of studies on rats, that specific neurons fire when navigating a horizontal plane but the use of certain neurons in 3D (adding upwards and downwards) had eluded them until today’s findings were published in the journal Nature today.
“There are even some cells that are sensitive to a certain combination of dimensions,” Finkelstein says. “For example, they’d only fire if the bat was pointing its head at a specific direction and pitching its head upwards.”
As you’re picturing this 3D compass, get the idea of a sphere out of your head, the data doesn’t fit it. Rather it is a mental-coordinate system that resembles a donut according to the study. East-facing cells and west-facing cells firing together when the bat flips does not work on a sphere, only a donut. Make sense? Not really? You’re not alone.
“Frankly, at first I found the concept pretty hard to grasp,” says Dave Rowland, a neuroscientist at the Centre for Neural Computation, in Trondheim, Norway who was not involved in the study but did read it prior to publication.
“It’s not that bats think of their world as donut-shaped, or there’s anything donut-shaped in their brain. This is just the topology that best fits for us to conceptualize what’s going on,” he told Popular Mechanics.
Finkelstein believes that the study could ultimately solve the problems of vertigo that causes about 15% of all general aviation accidents.
“Understanding the basic properties of the compass, and what happens when it malfunctions, could potentially lead to new methods for preventing these accidents,” he said.