Neuroprosthetics for Monitoring
Whilst it is certainly true that neuroprosthetics do not have to be limited to simply thought interface devices, by and large, they have been. The other side of neuroprosthetics, have been ignored. That other side being a system implanted into the brain, in order to not interface with the mind, but continuously monitor the health of the brain.
The first such neuroprosthetic, to be solely interested in tracking over time, the continued health of the brain, is a tiny, tightly wound tube, a lab-on-a-chip that has been taken and folded back upon itself, twirled into a spiral, for minimum surface area.
Researchers at the University of Cincinnati created it, a lab-in-a-tube. A tube was chosen, so that it can not just monitor the status of the brain, it can act, if necessary - pumping fluid both into the cranium, and siphoning off excess. Its designed to maintain the state of the intracranial environment following brain injury, and is placed through a single hole drilled in the skull.
In theory, it is designed for long-term implantation. Whilst the current models will not be, it is not at all hard to picture this, especially given the capabilities. The lab-on-a-tube can measure pressure, oxygen, temperature and glucose information as well as drain CSF simultaneously. It does this, because inside the spiral, which itself is wrapped round the tube, are layer upon layer of sensors, each layer detecting a different chemical.
Kapton film with glucose, oxygen and temperature sensors, and parylene microchannels were stacked, bonded and rolled spirally to form the layering, which in turn wrapped around a watertight silicone tube. Because the film is wrapped in a spiral, it adapts in real-time as the tube is expanded or contracted. Implantable via a tiny drill-hole, the tube can be expanded once inside, to the desired diameter.
The whole point is continuous real-time telemetry of the status of the brain's environment, with the option to remove excess fluid if required. That is as far as the capabilities of the current unit go, but is not the end of the capabilities of the paradigm.
As we continue to experiment ever more intrusively with the inner workings of the brain, neuroprosthetics such as this, designed to monitor the working environment of the brain, rather than the brain itself, are going to become ever more vital. In the short term, monitoring changes following brain injury is an obvious goal, but the next step from that would be implantation in those who can expect the likelihood of concussion in their daily working lives. As a longer-term solution, the ability to drain fluid if pressures build within minutes of an injury, could definitely preserve cognitive ability. Troops, law enforcement individuals, and professional boxers would be an obvious market segment.
Further to that, as the devices are implanted against the brain, they are not exactly tamper-friendly, and a fluidic lab, continually checking the chemical composition of the fluid, would be an ideal way to monitor those hopelessly addicted to chemical substances.
Of course, there is also the use in immersive VR - to serve as an early warning of a build-up of undesirable chemical compounds such as stress hormones, indicating when its time to disconnect the person gently, from their current simulation.