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“If cells are dreaming, [these images] are what the cells are dreaming about,” neuroscientist Carlos Ponce told The Atlantic. “It exposes the visual vocabulary of the brain, in a way that’s unbiased by our anthropomorphic perspective.”

Some neurons responded to images that vaguely resembled objects that the scientists recognized, suggesting that the researchers identified the specific neurons that corresponded with particular real-world objects. A blur that resembled a monkey’s face accompanied by a red blotch may have corresponded to another monkey in the lab that wore a red collar. Another blur that resembled a human wearing a surgical mask may have represented the woman who took care of and fed the lab’s monkeys, who wore a similar mask.

Other images that the monkey neurons responded to the most were less realistic, instead taking the form of various streaks and splotches of color, according to The Atlantic.

Even during such routine tasks as a daily stroll, our brain sometimes needs to shift gears, switching from navigating the city to jumping out of the way of a bike or to crossing the street to greet a friend. These switches pose a challenge: How do the brain’s circuits deal with such dynamic and abrupt changes in behavior? A Weizmann Institute of Science study on bats, published today in Nature, suggests an answer that does not fit the classical thinking about brain function.

“Most brain research projects focus on one type of behavior at a time, so little is known about the way the brain handles dynamically changing behavioral needs,” says Prof. Nachum Ulanovsky of Weizmann’s Brain Sciences Department. In the new study, he and his team designed an experimental setup that mimicked real-life situations in which animals or humans rapidly switch from one behavior to another—for example, from navigation to avoiding a predator or a car crash. Graduate students Dr. Ayelet Sarel, Shaked Palgi and Dan Blum led the study, in collaboration with postdoctoral fellow Dr. Johnatan Aljadeff. The study was supervised by Ulanovsky together with Associate Staff Scientist Dr. Liora Las.

Using miniature wireless recording devices, the researchers monitored neurons in the brains of pairs of bats that had to avoid colliding with one another while flying toward each other along a 135-meter-long tunnel at the high speed of 7 meters per second. This amounted to a relative speed—that is, the rate at which the distance between the bats closed, or the sum of both bats’ speeds—of 14 meters per second, or about 50 kilometers an hour.