Fish Have a Brain Microbiome. Could Humans Have One Too?

Scientists have long assumed that bacteria can’t survive in the human brain.

Scientists at the University of New Mexico discovered communities of bacteria thriving in salmon and trout brains.

Many of the microbial species have special adaptations that allow them to survive in brain tissue, as well as techniques to cross the protective blood-brain barrier.

Researchers have long been skeptical that the brain could have a microbiome because all vertebrates, including fish, have a blood-brain barrier.

Researchers found a subset of microbes that didn’t appear elsewhere in the body.

They hypothesized that these species may have colonized the fish brains early in their development.

Even in small numbers, Link said, resident microbes could influence our brain metabolism and immune systems.

If they are truly present, this would suggest an extra layer of neurological regulation that we didn’t know existed.

The more interesting question is: “Are they all there for a reason, or are they there by mistake?”.