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Simulated 'Frankenfish Brain- Swaps'

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Simulated 'Frankenfish Brain- Swaps' IN CONCLUSION How can different-sized people perform identical fine-motor tasks equally well, such as hitting a baseball or sending a text? In a study of the connection between brain, body and locomotor movement, researchers simulate “brain swaps” in fish to find out. swimming performance. ribbon fin could be used as a proxy of the SIMULATED Researchers say the findings provide neural controller applied by the central ‘FRANKENFISH BRAIN- new evidence that animals can lean on nervous system,” explained Ismail Uyanik, feedback from the senses to aid the assistant professor of engineering at SWAPS’ REVEAL interplay of the brain, body and stimulus Hacettepe University, Turkey, and former SENSES CONTROL from their external environment in postdoctoral researcher involved in the guiding locomotor movement, rather than study at NJIT. “The data allowed us to BODY MOVEMENT depending on precise tuning of brain estimate the locomotor dynamics and to circuits to the mechanics of the body’s calculate the controllers that the central lenty of fictional works like Mary muscles and skeleton. nervous system applies during the control Shelly’s Frankenstein have explored “What this study shows is the deep of this behavior.” the idea of swapping out a brain role of sensory feedback in everything “We logged nearly 40,000 ribbon-fin Pfrom one individual and transferring it into we do,” said Eric Fortune, professor at movements per fish during their shuttling a completely different body. However, a NJIT’s Department of Biological Sciences to get the data we ended up using to team of biologists and engineers has now and author of the study, funded by the help build models of each fish’s locomotor used a variation of the sci-fi concept, via National Science Foundation. “People plant and controller,” added Fortune. computer simulation, to explore a core have been trying to figure out how the With their models, the team began brain-body question. animal movement works forever. It turns computationally swapping controllers and How can two people with vastly out that swapping brains of these fishes is plants between the fish, observing that the different-sized limbs and muscles perform a great way to address this fundamental brain swaps had virtually no effect on the identical fine-motor tasks equally well, question and gain a better understanding models’ simulated swimming behaviors such as hitting a baseball or sending a for how we might control our bodies.” when they included sensory feedback text? Is it a unique tuning between our Using experimental tanks outfitted data. However, without the sensory brain and nervous system with the rest with high-res cameras in the lab, the feedback data included in the models, the of our body that controls these complex researchers tracked the subtle movements fishes’ swimming performance dropped off motions, or is feedback from our senses of three glass knifefish of different shapes completely. “Essentially, sensory feedback taking charge? and sizes as they shuttled back and rescues them,” said Fortune. In a new study featured in the journal forth within their tunnel-like refuges — a The team says the findings could also eLife, researchers have computationally common behavior among electric fish that help inform engineers in the design of modeled the various brains and bodies includes rapid and nuanced adjustments future robotics and sensor technology. of a species of weakly electric fish, the to produce sensory information that the “We want to be able to make robots glass knifefish (Eigenmannia virescens), fish need for keeping a fixed position that perform as well as humans [in to successfully simulate “fish brain within the safety of their hidden habitats, controlling body movement], but we transplants” and investigate. also known as station-keeping. need better control algorithms, and that’s The team’s simulations, which involved The team collected various sensory what we are getting at in these studies,” swapping models of the fishes’ information and kinematic measurements linked said Fortune. n processing and motor systems, revealed to the exercise — most notably, the that after undergoing a sudden jump into micromovements of the fishes’ ribbon-like Author: Jesse Jenkins is an NJIT Magazine the different body of their tank-mate, the fins that are critical to locomotor function contributing writer. “Frankenfish” quickly compensated for during shuttling activity — and applied the brain-body mismatch by heavily relying the data to create computer models of the on sensory feedback to resume control brain and body of each fish. of fine-motor movements required for “We showed that movements of the .
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