A team of scientists stimulated the brain using electrodes implanted on its surface coaxing their brains to see letters that weren’t there.
The team behind the research sent patterns of electricity across subjects brains, tracing out shapes that people could ‘see’. The technique worked on both sighted and blind people who had lost sight in adulthood.
The research, published in Cell, is an exciting glimpse at the life-changing impact the development of ‘visual prosthetic’ tech could have. In theory, the new tech has the potential to restore damaged vision.
The team were able to successfully craft letters using electrical currents. The technique relies on ‘phosphenes’, these tiny specks of light often appear in our vision without light entering our eyes (think seeing stars when you rub your eyes!). This is because they are a quirk of how we process our vision. They are not actually there.
The phenomenon was first noted by Alcmaeon, an ancient Greek philosopher. However, it wasn’t until the 1960’s the idea of trying to generate these patterns intentionally as a visual prosthetic was developed.
Even at a very basic level of ‘single pixels’ being stimulated, the technique could help blind people navigate better using a similar strategy to cochlear implants.
While the study shows the technology is still in its very early stages, the research is very promising.
Published as “Dynamic Stimulation of Visual Cortex Produces Form Vision in Sighted and Blind Humans” in Cell.