Image of the neural recording process, courtesy of Lund University.
A collaboration between Swedish and Italian researchers that aimed to analyze how the brain interprets information from a virtual experience of touch, created by a prosthetic finger with artificial sensation, has resulted in a new method for measuring brain health. The work has implications for sensory-capable prosthetic hands and to evaluate treatments for neurological diseases like Alzheimer’s, stroke, and Parkinson’s. The study desribing their work was published April 4 in Scientific Reports.
“We were able to measure the cooperation between neural networks in a very precise and detailed way. We can also see how the entire network changes when new information comes in,” said neuroscience researcher Henrik Jörntell, PhD, a senior lecturer with Lund University, Sweden.
The group—from Lund University and Scuola Superiore Sant’Anna (SSSA), Pisa, Italy—generated artificial touch experiences with a bionic fingertip currently used for robotic upper-limb neuroprostheses. These artificial touch experiences were provided to the touch sensor nerves of the skin in a rat, as a kind of neuroscientific playback of information to the brain. Using a high-resolution analysis of how individual neurons and their connected brain networks process this touch information, designed by neurocomputational scientist Alberto Mazzoni, PhD, a post-doctoral fellow at SSSA, and physics scientist Anton Spanne, a doctoral student at Lund, the groups got an unexpected insight into the brain representations of the external world experienced through touch. Single neurons in the brain can convey more information than was previously thought and can interact to generate potentially super-rich representations of sensory stimuli.
“This knowledge will be embodied into a novel generation of sensitive robotic hands able to convey fine tactile information to amputees,” said Calogero Oddo, PhD, an assistant professor of biorobotics at SSSA. “Such robotic arms with human-like richness of touch are also being used to perform complex tasks in surgical robots, rescue, services, and industry.”
The prosthesis was made to touch various objects that generate different patterns of electrical signals. These were subsequently fed into a part of the paw of an anesthetized rat, and then, with the help of electrodes in the brain and advanced analytical techniques, the researchers could measure the reactions in the rat’s neuronal networks. The researchers recorded the reactions at very high resolution, as the electrical signals were carefully controlled and could be delivered multiple times with exact reproducibility.
For the Italian group, and for all others involved in research on advanced prostheses, the method provides a new tool for exploring the sensations the prostheses can provide. For the Lund researchers, the method provides a tool for studying how neurons cooperate inside a healthy brain and in animal models with different neurological diseases.
Editor’s note: This story was adapted from materials provided by Lund University.
