In-Ear Bioelectronic May Replace Leading Brain-Computer Implants

(Posted on Wednesday, August 9, 2023)

This article was originally published on Forbes on 8/9/23.

This story is part of a series on the current progression in Regenerative Medicine. This piece discusses advances in brain-computer interfaces.

In 1999, I defined regenerative medicine as the collection of interventions that restore to normal function tissues and organs that have been damaged by disease, injured by trauma, or worn by time. I include a full spectrum of chemical, gene, and protein-based medicines, cell-based therapies, and biomechanical interventions that achieve that goal.

In the coming years, a new in-ear bioelectronic called SpiralE may be the next step toward seamless brain-computer interfaces. When we interact with a computer, smartphone, or tablet, we interact with the device through various forms, including a keyboard, touch screen, or even voice commands. More recently, devices may be controlled by something as simple as eye movement. As technology becomes more intertwined with our daily lives, the brain-computer interface becomes a more critical part of daily activity.

Brain implants have recently allowed users to control electronic equipment with thought or, more precisely, electronic nerve impulses. This seems the logical next step in widespread public brain-machine interfaces, but the technology needs to be revised by form-factor limitations. The implants are typically accompanied by inconvenient or medically risky devices, including bulky headbands, microneedle-invasive devices, etc. These accompaniments make daily use impractical for the average user.

Dr. Zhouheng Wang and colleagues from Tsinghua University in Beijing may have developed a solution. In a recent study in Nature, the researchers describe a new in-ear bioelectronic they call SpiralE. In place of a bulky headband or invasive needle device, SpiralE is a small electronic device made of a flexible polymer that transmits electronic signals from the user to a computer.  Here we discuss this new technology and its impact on brain-computer interfaces.

SpiralE was developed with a driving goal: a comfortable, removable form factor with all the functionality of bulkier or more invasive devices. The device is comprised of multiple layers, all fixed to a cylindrical mold of 5.5 mm in diameter. For context, the leading wireless in-ear headphone is 15-20 mm long and wide.

The layers include electrothermal components, wiring, adhesion, and so on, all packed together in a memory polymer that molds to the ear canal of the user, maximizing comfort and stability. 

FIGURE 1: Pictures of SpiralE conformally adapting to the inner wall of the ear canal. Upper-right inset is a photograph captured by a medical endoscope. Lower-right inset shows the irregular three-dimensional structure of SpiralE after removal from the ear.

While many brain-computer interface devices require an invasive brain implant to communicate electronic signals to a computing device, the SpiralE is entirely self-contained. It can be removed when not in use by the user in seconds and can just as easily be reinserted. 

Notably, the spiral design allows for unimpeded hearing while in use. The spiral design allows for an unobstructed ear canal, and auditory tests run by Dr. Wang and colleagues confirm that not only does the user continue to hear unobstructed at cocktail party noise levels, but the device itself continues to function with 84% accuracy in high volume environments.

It is unclear how long the shelf life is for the SpiralE device, though the lack of battery in the layered design suggests that the only need for replacement would be regular wear and tear from daily use.

Another factor that may fall under SpiralE’s positive attributes is cost. While invasive implant procedures and bulky headband designs may be cost-prohibitive for many, the compact and simple design of SpiralE will keep production costs reasonably low. While more elaborate and invasive brain-computer interfaces may cost thousands, if not tens of thousands of dollars, I speculate SpiralE could cost less, if not significantly less, for the average consumer.

Beyond regular use by consumers, SpiralE has the potential to revolutionize regenerative medicine, including applications in motor and language rehabilitation and assistance. While the device is far from commercially available, I look forward to hearing about the progress of SpiralE in the coming months and years as we move towards a more connected and accessible world.

Read the original article on Forbes.