Brain implant could be used in reactivating paralysed limbs

A brain implant developed at the University of Michigan is claimed to use the body’s skin like a conductor to wirelessly transmit the brain’s neural signals to control a computer.

The implant is called the BioBolt and unlike other neural interface technologies that establish a connection from the brain to an external device such as a computer, it’s minimally invasive and low power, said principal investigator Euisik Yoon, a professor in the University of Michigan College of Engineering, Department of Electrical Engineering and Computer Science.

Currently, the skull must remain open while neural implants are in the head, which makes using them in a patient’s daily life unrealistic, said Kensall Wise, the William Gould Dow Distinguished University professor emeritus in engineering.

According to a statement, BioBolt does not penetrate the cortex and is completely covered by the skin to reduce risk of infection. Researchers believe it’s a critical step toward allowing a paralysed person to ’think’ a movement.

The ultimate goal is to be able to reactivate paralysed limbs by picking the neural signals from the brain cortex and transmitting those signals directly to muscles, said Wise.

Another promising application for the BioBolt, for which a patent has been filed, is controlling epilepsy and diagnosing diseases such as Parkinson’s.

According to the university, the BioBolt looks like a bolt and is about the circumference of a small coin, with a thumbnail-sized film of microcircuits attached to the bottom.

It is implanted in the skull beneath the skin and the film of microcircuits sits on the brain. The microcircuits act as microphones to ’listen’ to the overall pattern of firing neurons and associate them with a specific command from the brain. Those signals are amplified and filtered, then converted to digital signals and transmitted through the skin to a computer, Yoon said.

Another hurdle to brain interfaces is the high power requirement for transmitting data wirelessly from the brain to an outside source.

BioBolt is said to keep the power consumption low by using the skin as a conductor or a signal pathway.

Eventually, the hope is that the signals can be transmitted through the skin to something on the body, such as a watch or a pair of earrings, to collect the signals, said Yoon, eliminating the need for an off-site computer to process the signals.