Scientists using cutting-edge brain imaging technology finally know how that new idea pops into your head and may even be able to read the thought by looking at your brain. Researchers at Carnegie Mellon University observed 16 participants' brains as they learned about the habitat and eating habits of eight extinct animals, Wired reports. As participants underwent a one-hour, mini-tutorial on the animals, functional magnetic resonance imaging showed changes in specific parts of the brain, along with a "unique activation signature" for each animal. Incredibly, a computer program was then able to determine which animal a participant was thinking about just from observing their brain. In other words, scientists could read the participants' minds.
"Each time we learn something, we permanently change our brains in a systematic way," says the lead author, whose research is published in Human Brain Mapping. For example, anyone who read about the discovery of the olinguito "permanently changed their own brains," a researcher explains in a press release. "When people learned that the olinguito eats mainly fruit instead of meat, a region of their left inferior frontal gyrus—as well as several other areas—stored the new information according to its own code." Animals with similar diets or habitats elicited similar activation signatures, and a property of an animal stayed in the brain once it was learned, even after several new animals were introduced, suggesting a neural durability of the subjects we learn. Researchers say the study could help develop new teaching methods and give insights into how knowledge is supposedly erased due to conditions like dementia. (Check out the gruesome way a tribe became immune to brain disease.)