Every thought is a “break” of DNA

In recent years, neuroscientists have been amazed to realize that neurons, when they activate, break the strand of DNA that they protect at their heart, in order to accelerate their reactivity. And this has just been shown in the hippocampus, a region of the brain, during long-term memory.

Hervé Poirier, editor-in-chief of the scientific magazine Epsiloon, tells us about a completely astonishing discovery… A dizzying neuro-genetic process.

franceinfo: It is by breaking our DNA that memories are engraved in the brain. Explain to us.

Hervé Poirier: The experiment was carried out by American biologists on mice, which were trained to associate a very particular place with a small electric shock, so that when they were later reintroduced to this place, they remembered it and Are afraid. Well it’s very surprising, yes.

Analysis of the hippocampus of these mice, the key area of ​​their memory, demonstrates that during this somewhat unpleasant learning, the double strand of DNA hidden at the heart of the neurons involved breaks into multiple pieces. Faced with all these pieces of DNA wandering around, neurons activate and an inflammatory response is triggered to repair everything.The scene repeats itself during learning.

And this cycle of genetic damage and repair allows memories to form and last. And it would be the very way in which DNA breaks, which would encode the information to be memorized, the researchers suggest… In short, to memorize something well, you have to break your DNA! Staggering.

But it’s still a bit dangerous to break your DNA, right?

Yes, and eIn general, this is not recommended. This opens the door to cancers and neurodegenerative diseases, such as Parkinson’s or Alzheimer’s. It is Elsa Suberbiellea young French neurobiologist from the CNRS, who, 10 years ago, was the first to think that the neuron breaks its DNA in this way, to accelerate its activity. She told us that at the time, few colleagues were ready to accept the idea.

10 years later, there is consensus: at the slightest word that comes to mind, at the slightest image, crack, the DNA of our neurons breaks. This facilitates and accelerates the weaving of synapses between neurons: the word, the image, the thought, are imprinted in the brain. And this principle has now also been demonstrated for long-term memory.

A path to understanding neurodegenerative diseases?

Certainly. During our life,Neurons are capable of breaking their DNA millions of times, but we can imagine that the repair mechanisms become less and less infallible over time. And the Genetic errors accumulate.

But we can only admire in front of the incredible machinery housed under our skulls: while listening to this post, in the nucleus of your neurons, your DNA was broken, then repaired. Allowing you to realize the magnitude of this puzzling discovery.