Skip to main content
Ages 13+
Under 13
Neurons overlaid with stars in a galaxy.

On the Striking and Strange Similarity Between Neurons and Stars


Imagining the stars, in light of a new scientific study of the structures making up both the brain and the universe, results in an unexpected poetry.

The brain is one of the most complex of all the systems that humankind has confronted. It compares, in fact, only to the very universe we inhabit. Hundreds of billions of neurons form webs that perplex us in their beautiful mystery and remind us of the complicated systems making up the universe, and its billions of stars and galaxies.

This dramatic similarity led Franco Vazza and Alberto Feletti, an astrophysicist and a neurologist respectively, to compare both systems. The results of their study are fascinating. They’ve made evident not only that there is an impressive similarity in quantitative terms, but that their structures and their organization are much more similar than had ever been conceived.

Their spectacular task entailed overcoming remarkable obstacles, beginning with the difficulty of comparing information from a telescope with that from a microscope. And the most obvious problem: how does one contrast such immensely different scales? (Tens of billions of light years versus the minimal measures of a neuron in the brain.) Vazza and Feletti’s study finally equates figures of space in which billions of galaxies coexist, and of which only one is home to these billions of brains, and these, in turn, are made up of billions of neurons. This information allows us to take in one extraordinary truth: the number of neurons in our brain and the number of galaxies in the universe are numerically comparable, and their organizations are equally complex.

horsehead nebula photographed by the Hubble telescope.

At a non-scientific glance, before the human eye, the structure of a cosmic network looks impressively similar to a micro-photograph of the brain. Is this resemblance merely the result of our tendency to find meaningful patterns in any information we perceive? The answer is no. Statistical analysis proves that these systems do present quantitative similarities, in addition to those more immediately apparent.
One of the most effective ways to compare the complexity of cosmic and cerebral systems, according to the two researchers, is to study how predictable their behaviors are. This can be calculated by counting the number of bytes of information necessary to design the simplest computer program capable of making such predictions in both examples. The results actually match up impressively.

To put it relatively simply, the figures from this experiment imply that the amount of information that can be stored by a human brain (that is, the memories of a person’s entire life) can be coded in the same way as the distribution of galaxies in the universe.

Subject to the limitations that still exist in making precise measurements of the universe (at least what we know of it) and also of the human brain, the metaphor reflecting this complicated study implies a similarity that would be obvious were it not for its deep beauty. It’s a metaphor that speaks to us of inner galaxies and allows us to intuit a wisdom and a connection between all the kingdoms in existence in the universe, at once the most immense with the very smallest.


*Images: 1) UCI Research - flickr / Creative Commons; 2) The Horsehead Nebula / Wikimedia Commons

Related Articles