Controlling Brain Activity with a Bluetooth Implant and Smartphone

A research team from the United States and Korea has recently created a small brain implant that is controlled by a smartphone and can manipulate neural circuits. This innovative solution has the potential to facilitate efforts in uncovering various brain diseases, including depression, addiction, pain, Alzheimer’s, and Parkinson’s. A paper regarding this work, conducted by researchers from the Korea Advanced Institute of Science and Technology (KAIST) and the University of Washington in Seattle, was published on August 5 in Nature Biomedical Engineering.

This Bluetooth-enabled device uses replaceable plug-like drug cartridges to target neurons with drugs and light. The chemical and optical neuromodulation that this wireless device is capable of “has never been achieved before,” according to lead author Raza Qazi, researcher from KAIST and University of Colorado Boulder.

Qazi feels this creation trumps existing methods used by neuroscientists to deliver drugs and light to the brain, which involves metal tubes and optical fibers. These tools are rigid and can damage the brain’s soft tissue over time. In addition, this equipment limits the patient’s movement because of the physical, wired connections, making them unsuitable for long-term use.

Researchers have attempted to make this system less damaging to brain tissue by using soft probes and wireless systems, but these prototypes have failed to deliver drugs for a long period of time and require complex control setups.

Smartphone-Controlled Drug Delivery

To create their smartphone-enabled solution, the researchers had to address the fact that the implant’s drug supply would not last forever. The research team dealt with this by creating a neural device with a replaceable cartridge that contains the drug. In doing so, they enabled neurologists to study the same brain networks for several months without depleting the drug supply.

These drug cartridges were integrated into a brain implant with a soft probe that is as thin as a human hair. Containing microfluidic channels and small LED lights, this brain implant for mice is capable of unlimited drug doses and light delivery. The implant is regulated via a smartphone, allowing researchers to trigger precise combinations and sequences of drug and light delivery. In animal models these stimuli can be triggered with the target outside of the laboratory, allowing researchers to wirelessly instill changes in the animal’s brain while in its natural habitat.

“This revolutionary device is the fruit of advanced electronics design and powerful micro and nanoscale engineering,” explained Jae-Woong Jeong, professor of electrical engineering at KAIST. “We are interested in further developing this technology to make a brain implant for clinical applications.”

Fellow researcher Michael Bruchas, professor of anesthesiology and pain medicine and pharmacology at the University of Washington School of Medicine, also feels their device will be impactful in the medical space.

“It allows us to better dissect the neural circuit basis of behavior, and how specific neuromodulators in the brain tune behavior in various ways,” he said. “We are also eager to use the device for complex pharmacological studies, which could help us develop new therapeutics for pain, addiction, and emotional disorders.”

Researchers under Jeong at KAIST work to create electronic devices that can be worn and implanted. Bruchas’ lab at the University of Washington, on the other hand, strives to study neural circuits responsible for stress, depression, pain, addiction, and other neurological disorders. The collective work from these two groups took place over a three-year period, with many different design prototypes being created before the successful result. This model was validated in freely moving mice, effectively controlling their locomotor control for over four weeks. The authors conclude that this implant system could potentially “contribute to uncovering the basis of neuropsychiatric diseases.”