An international group of scientists has demonstrated that it is possible to use the power of magnetism to control the movement of mice. Using a technique called magneto-thermal stimulation, the researchers were able to stimulate the brains of the mice to prompt them to run, turn around, and temporarily halt all motion.
“We have developed an interface capable of sending signals to individual neurons deep inside the brain,” Arnd Pralle, professor of physics in the University at Buffalo College of Arts and Sciences, told Digital Trends. “It requires sensitizing the target neuron to heat and attaching magnetic nanoparticles to these neurons. If an animal then enters an alternating magnetic field, the nanoparticles warm up, opening an ion-channel, and activating the neuron. After the initial delivery of the ion-channel and the nanoparticles — which is done through a needle about the size of a human hair — the method is noninvasive, meaning there are no wires or connectors going to the brain.”
It is this latter point that is most significant. Similar techniques have been previously demonstrated, using light instead of magnetism and heat to activate the brain cells. However, these approaches require the permanent presence of minute fiber optic cables in the brain. The use of magnetism instead allows neurons to be stimulated remotely.
Between this and other related projects — such as the various brainwave-reading technologies allowing people to control prosthetic limbs or drones with their mind — Pralle says that it’s an exciting time to be working in the field.
“We are living a decade of the brain distinctly different from the first decade of the brain, the 1990s,” Pralle said. “There are several tools, including the one developed by us, which enable researchers to map neurocircuitry with emotions and behaviors. Currently this permits scientists to being understanding how our brain compute information, and how responses are encoded by the circuits. We are just at the beginning of these discoveries, and it likely will take a least a decade or more to unravel brain circuitry. However, eventually magneto-thermal neurostimulation and silencing and similar techniques will provide direct brain interfaces for artificial senses; perturbation for deep depression and other mood disorders; and therapeutics for age-related or accident-caused neurodegenerative diseases.”
A paper describing the work was published in the open-source, peer-review journal e-Life.