A team at Northwestern University has achieved a major breakthrough in the intersection of neurobiology and bioelectronics, developing a wireless device that uses light to "talk to the brain." This technology, which uses light to directly transmit information to the brain, is considered an important step towards building future wireless brain-computer interfaces. The related paper was published on August 8 in the journal *Nature Neuroscience*.
This tiny device is soft and flexible, and can be implanted under the scalp, close to the surface of the skull. It sends precisely controlled light patterns through the bones, thereby bypassing the body's natural sensory pathways and directly activating specific groups of neurons in the cerebral cortex.
This technology builds upon the team's previous development of the first wireless, battery-free, fully implantable optogenetic device, but with key upgrades. The new device is equipped with an array of 64 tiny LEDs, each only as thick as a human hair, which can be wirelessly programmed to send complex sequences of light to the brain.
This multi-regional, programmable design simulates the distributed brain activity patterns in natural sensory experiences, so that the information transmitted is no longer a simple on/off signal, but rather a distributed cortical network activity similar to that in natural sensory experiences.
During the experiment, the team used tiny, precisely timed light pulses to stimulate specific groups of genetically modified neurons deep in the brains of mice. These mice quickly learned to interpret specific light pulse patterns as meaningful cues. Even without external sensory input such as vision, hearing, or touch, they were able to make decisions using these artificial signals and accurately complete tasks such as searching for rewards.
John A. Rogers, a pioneer in bioelectronics at Northwestern University, said that by integrating a micro-LED array with a wirelessly powered control module, they have created a new system that can be programmed in real time, is completely hidden under the skin, and does not affect natural behavior.
This technology shows great promise for applications in the medical field, including providing sensory feedback for prostheses, providing artificial input for visual or auditory prostheses, modulating pain perception without the use of drugs, and assisting in rehabilitation training after stroke or trauma. The team is currently planning to test more complex stimulation patterns and explore the limits of the brain's ability to learn different patterns.
[Editor's Note]
Researchers have developed a wireless device that allows the brain to communicate directly with light, requiring no batteries or wires, much like a lightweight Bluetooth headset. This device uses light to transmit information to the brain; even without other sensory pathways or with damaged organs, specific areas of the brain can still be activated by complex light sequences. This technology opens new possibilities for multiple fields, providing realistic tactile feedback for prosthetic users; sending specific signals to the brain to allow visually impaired individuals to perceive light, and hearing-impaired individuals to perceive sound. With technological advancements, the way the human brain interacts with machines and even the world may be redefined.
(Original title: A significant step in building the future of wireless brain-computer interfaces: Wireless devices use light to "talk to the brain")
