Scientists have managed to implant sensory information directly into people’s brains, allowing them to find their way around a maze without needing to actually see it. Using a technique called transcranial magnetic stimulation (TMS), the researchers caused participants to experience flashes of light inside their heads, letting them know that they had to change direction.
For the experiment, volunteers had to guide an avatar around a virtual maze that was completely hidden from view. At certain intervals they were asked whether they wanted to keep walking straight or turn to the side.
To let players know that their avatar had reached a wall and needed to alter its course, the team used TMS to stimulate the visual cortex of their brains, causing them to “see” a flash of light called a phosphene. These are often experienced when we put pressure on our closed eyes by rubbing them, and occur despite the fact that no light is actually entering the eye.
Using this method, participants were able to choose the correct option on 92 percent of steps in a series of different mazes. Reporting this result in the journal Frontiers in Robotics and AI, the study authors claim that TMS – which is a non-invasive technique that involves applying small electric currents to the brain from outside the skull – could help to fill in the gaps in sensory perception experienced by blind or deaf people.
Though the system used in this experiment is fairly rudimentary, with phosphenes helping to convey simple yes-no commands, the researchers write that “as the technology advances, we anticipate that more sophisticated transmission of information may become possible.”
First, however, it will be necessary to develop portable TMS devices, as the machines used in this study are far too large to for this technique to be practical.
Yet the team insist that “as this aspect of the technology improves, the paradigms presented here could be useful, for example, in developing a non-invasive sensory prosthesis for the blind.”