Researchers at Michigan State University have made a surprising discovery about the enteric nervous system of the human gut, the so-called "second brain." Not only do they find that this second brain does indeed exist, but that it is remarkably independent .
That is, the intestines could perform many of its usual tasks even if it were somehow disconnected from the central nervous system. And the number of specialized cells of the nervous system, namely neurons and glia, that live in a person’s gut is roughly equivalent to the number found in a cat’s brain .
Gulbransen and his team have now shown that glial cells (unlike neurons, glial cells do not have axons, dendrites, or nerve conduits) play a much more active role in the enteric nervous system than was initially believed moment .
In computer language, the glia would be the logic gates. Or, for a more musical metaphor, the glia don’t carry the notes played on an electric guitar, it’s the pedals and amps that modulate the pitch and volume of those notes.
In recently published research , researchers revealed that the glia acts in a very precise way to influence the signals carried by neural circuits. This discovery could help pave the way for new treatments for intestinal diseases .
The glia could also be involved in several other health conditions, including intestinal motility disorders, such as constipation, and a rare disorder known as chronic intestinal pseudo-obstruction.
This new study thus creates a more complete, if more complicated, picture of how the enteric nervous system works. Something not so strange if we take into account, as the neurobiologist Michael Gershon explains in his book The Second Brain , that 95% of all the serotonin that runs through our body is found in the intestine, our second brain.