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April 3, 2020

Fish Switch

How can people with vastly different-sized limbs and muscles perform identical fine-motor tasks equally well? Scientists simulated a brain swap to find out.

Credit: National Science Foundation/Karson Productions

Brain exchange.

I'm Bob Karson with the Discovery Files, from the National Science Foundation.

People come in different shapes and sizes; yet can produce similar movements. Is that because our brains and nervous systems are finely tuned to our own muscles and skeleton? Or because we compensate for differences by relying on feedback from our senses to guide our movements.

To find out, researchers at New Jersey Institute of Technology and Johns Hopkins took a brain out of one fish and implanted it into another. (Sound effect: thunderclap, medieval lab, bubbling, electric arcs). No, they didn't go all 18th Century and create some bizarre 'Frankenfish.' They did it with computer modeling.

Using experimental fish tanks with high-res cameras, they tracked 40,000 micromovements for each of three real live glass knife fishes, along with wave patterns created by their ribbon fins. With this data, the researchers created computer models where they could 'swap out' the brains of virtual fish.

As long as the fish received sensory feedback, swimming behavior was unaffected. Without getting sensory data -- (Sound effect: gameshow-type buzzer wrong!). (Sound effect: Pac man loser sound) it was as if the fish couldn't adjust to having the wrong brain.

This 'catch of the day' on the deep role of sensory feedback could help engineers design future robotics and sensor technologies. (Sound effect: producer on slate mic: "you wanna wrap it up, bob?")

Ok, getting some 'sensory feedback' from my producer, (Sound effect: producer under: "three") I gotta move, we're almost ou... (Sound effect: gets cut off)

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