ICYMI: Fish Brains Use Different Navigational Systems than Us

iStock.com via MirekKijewski

Researchers performed brain surgery on 15 goldfish to study their neuronal activity and the underlying brain mechanisms that allow the aquatic animal to navigate its fishbowl.

Neuroscientists surgically implanted electrodes the diameter of a hair strand onto the half-inch brain of a goldfish, pumping anesthetics and water into its mouth to keep it pain-free and breathing. A waterproofed recording device monitoring neuronal activity — buoyed by plastic foam — showed the closer the headgear-toting fish swam to the edges of their 2-feet, 6-inch tank, the more their brains' navigational cells lit up, according to the April 25 study published in PLOS Biology.

The researchers found fish use a slightly different navigational system than what mammals have been found to use — as described in 2014 Nobel Prize-winning research demonstrating almost all creatures had an inner GPS navigation system. Whereas mammals possess specialized neurons that create location pinpoints for mental maps, fish do not. Instead, they have a type of neuron that fires to alert them to an approaching obstacle or boundary. So, while mammals can pinpoint their exact location, fish determine their whereabouts by their relative proximity to objects or barriers.

Big Picture: Navigation skills are important to understand because they are tied to survivability when hunting food, seeking shelter, or fleeing predators. Studying it in fish, the largest group of vertebrates, may shed light on the evolution of navigation across many other creatures.

Read More: Why Researchers Turned This Goldfish Into a Cyborg. New York Times

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About the Author

Christine Won

Christine is a former staff writer/editor for BrainFacts.org. She is an award-winning investigative journalist with a background in daily news reporting and industry copywriting. A University of Illinois graduate, she holds a degree in news-editorial journalism and English.