Next Generation Implantable Neural Interfaces
Being able to control devices with our thoughts is a concept that has for long captured the imagination. Neural Interfaces or Brain Machine Interfaces (BMIs) are devices that aim to do precisely this. This is achieved by observing the electrical activity from the brain (originating from the neural activity), processing this to decode basic intention, and using this to control an external device, e.g. mouse cursor, wheelchair, prosthetic arm. The current approach to recording neural activity either uses non-invasive scalp-worn electrodes (e.g. electroencephalography – EEG), or invasive electrodes (e.g. penetrating intracortical – Utah Electrode Array). Non-invasive recordings tend to be extremely noisy due to fact the recording electrodes are relatively far away from the brain and record the activity from millions of neurons. As it is extremely challenging to extract any useful information (with sufficient speed) using such methods, implantable devices are being considered. Despite good progress (e.g. BrainGate), there are major challenges: (1) information transfer rate is low; (2) high day-to-day variability in recorded signals – requires frequent recalibration/training; (3) current devices are only partially-implantable (electrodes implanted with percutaneous connections to external electronics).
A team at Imperial College London led by Dr Timothy Constandinou is developing next generation implantable neural interfaces that directly address the challenges mentioned above. Key features of this technology are:
- Size reduction – New method for hermetic packaging of implantable medical devices: micropackaging provides a ~1000x reduction in volume compared to conventional metal-can-based packages
- Integration capability – Allowing for chronically-stable neural interfaces by combining CMOS microelectronics with wire-based electrodes.
- Ultra-high scalability – Distributed approach to achieving large scale millimetre-sized implantable devices
- Wireless connectivity – Distributed wireless powering and communication with multiple devices
+44 (0)20 7594 6867