This is the first complete map of the circuits of a brain

This is the first complete map of the circuits of a brain

Marta Zlatic , a mathematician and computer scientist at Johns Hopkins University, has joined an international team of neuroscientists to create a complete brain map of the fruit fly larvae. Specifically, of a part of the brain.

We are talking about approximately 1,700 of the 10,000 neurons contained in the entire brain of a larva . The part of the brain of the fruit fly larva used in the study roughly corresponds to the cerebral cortex in mammals.


Analysis of the map reveals connection patterns between six types of neurons that had previously been misinterpreted or were entirely unknown.

Still , while this study is an important step in understanding the human brain, there is still a long way to go : wiring alone does not fully explain how circuits generate behavior. For example, hormones also play a role.

In addition, the leap in complexity with respect to the larvae of the fruit fly is overwhelming: in just 1,400 grams of brain we house between 10 billion and 100 billion neurons (as many as the number of stars in our galaxy). Each neuron establishes between 5,000 and 50,000 connections with its neighboring cells. Which is equivalent to building a neural network intercommunicated by 100,000,000,000,000 connections.

As if that were not enough, neurons cannot be compared to a logic gate of a computer, but each neuron is a computer in itself , and also everything is continuously reprogrammed.

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For example, each time you learn a new skill, you strengthen the dendrites that connect to neurons that control the necessary muscles. As Marcus Chown writes in his book The Universe in Your Pocket :

The brain is a computer, yes, but of an amazing kind indeed. Whereas a conventional silicon-based computer performs a task according to the program that a human being has introduced to it, the brain has no external programmer. It is a computer that programs itself.