Researchers have succeeded in encoding musical “notes” in the brains of birds by manipulating the activity of their neurons. The birds then used these implanted “memories” to learn a new song he had never heard before.
In order to master language, the most effective tool is repetition. This is the technique used with human babies. They learn at the cost of much training, repetition and effort. But although language is a crucial step in our development, some components of its learning are still misunderstood. How does the brain manage to encode the necessary memories to imitate the sounds emitted by our dear parents? To try to understand it, researchers at UT Southwestern (USA) looked at songbirds. The details of the study are published in the journal Science.
Implant “memories” in the brain
On the zebra finches, more exactly. These birds do indeed in the same way as us to learn to communicate. Very early, the children listen to their father singing, memorize the notes, then try to repeat them. After tens of thousands of attempts, the boy finally manages to sing the same thing as his father.
The idea of this study was: to teach them a song by encoding notes directly into their brain. To do this, researchers activated a neural circuit using light pulses. The duration of each note corresponded to the duration during which the light was maintained. The shorter the exposure to light, the shorter the rating. And conversely.
“We do not teach the bird everything it needs to know – just the length of syllables in its song,” says Todd Roberts, lead author of the study. The two brain regions we tested in this study are just one piece of the puzzle. Nevertheless, the discovery is remarkable because it opens new avenues of research to identify more brain circuits that influence other aspects of vocalization, such as the pitch and order of each sound. ”
As predicted by the researchers, the small birds were able to transcribe the duration of the notes. These have been encoded in their brains. In other words, they had never heard them before.
If the human brain is actually more complex than that of the songbird, researchers hope nevertheless one day to use this knowledge to target speech-specific genes that are disrupted in patients with neurodevelopmental disorders.