News Neuroscience

Some healthy fish have bacteria in their brains

Microbes in animal brains are typically linked to disease

An illustration of a rainbow trout is shown from the middle of the fish's body to the fish's head

Brains are usually thought of as a bacteria-free zone. But that’s not the case for certain fish, including rainbow trout (illustrated) and other species in the salmon family.

Duane Raver/USFWS

By Erin Garcia de Jesús

Some fish have bacteria on the brain.

Wild and lab-grown members of the salmon family including European rainbow trout, Chinook salmon and Gila trout harbor active microbial communities inside their brains, researchers report September 18 in Science Advances.