"These new results are an important step towards demonstrating safety and efficacy of the device while recording and transmitting neural data in real time over a period of months. The device performance and quality of the data are very encouraging as we prepare next steps towards human clinical trials," said Shenandoah Montamat , MSc, who is managing the ABILITY project at the Wyss Center.
Two MEAs, each smaller than a pea, recorded the activity of individual neurons with an array of fine needles that penetrated the surface of the cortex. At this resolution it is possible to decode fine movement intention with high accuracy from very small brain areas. In a separate study, four ECoG grids, each about the size of a postage stamp, recorded signals from the surface of the cortex. ECoG electrodes cover a larger area of the brain than MEAs and measure the combined activity of nearby neurons with sufficient resolution to decode speech, in humans.
The ABILITY system records 128 channels of neural data at a frequency sufficiently high to observe communication between single neurons, known as action potentials, as well as the lower frequency synchronous activity of groups of neurons firing together, known as local field potentials. It wirelessly transmits the raw data through the skin using a high-speed optical link. Wearable components send the neural data to a computer with a wired connection. The wearable also wirelessly powers the implant through the skin via induction.
"The development of ABILITY draws on experience from a recent clinical case study that successfully enabled BCI communication for a person completely locked-in because of ALS," says Jonas Zimmermann , PhD, Senior Neuroscientist at the Wyss Center.
In that study , the patient learned to modulate neural activity to control speller software. The system used a wired connection to transfer data between implanted electrodes and an external computer through a percutaneous connection in the scalp.
"The study highlights the clinical need for breakthrough implant technology to improve ease of use for patients and caregivers," continues Zimmermann.
George Kouvas , MBA, Wyss Center Chief Technology Officer says: "At the Wyss Center we are addressing some of the major neuroscientific and engineering challenges that fully implantable brain-computer interfaces encounter during development. The result is a versatile technology like ABILITY that has the potential to help the BCI market grow."
Human clinical trials are now being prepared to assess ABILITY system performance and understand the acceptance of implantable BCIs by patients, caregivers, and healthcare professionals.
Topics covered in this release will be presented at the Society for Neuroscience meeting in San Diego 12-16 November 2022.
Saturday 12 November 1-2pm 059.01/T15 - ABILITY: feasibility and safety study in sheep of a fully implantable intracortical brain-computer interface
Saturday 12 November 2-3pm 059.02/T16 - ABILITY: a fully implantable device to acquire intracortical neural signals for clinical brain-computer interfaces
Saturday 12 November 4-5pm 059.08/U6 - Evolution of BCI performance over three years of recordings with intracortical microelectrode arrays in a complete locked-in syndrome patient
Saturday 12 November 1-2pm 059.09/U7 - Intracortical SSVEPs and auditory oddball for BCI control in a completely locked-in patient
Saturday 12 November 2-3pm 059.10/U8 - Evolution of performance and signal quality during the long-term use of an intracortical BCI
Monday 14 November, 4-5pm 389.24/HH10 - Analysis of different motor attempts from intracortical microelectrode arrays in a completely locked-in state patient