The main problem they don't talk much about, and why this isn't ready to go mainstream, is that those brain implants will decay over time.
The brain will build up scar tissue around the electrodes and render them useless. These are basically little needles put into a jell-o which then wiggles around all the time. This constantly irritates and damages the tissue. Your immune system hates this.
Even within months there's a significant decay. But, within 5-10 years most of the array becomes pretty useless. Of course, you can't replace it easily. And the damage to that area, while local, isn't reversible.
There's a lot of research on trying to make a brain implant that can last longer so that all of these treatments become viable. But we still have basically nothing.
Figuring out the required stem cell treatment to properly regenerate damaged nerves or creating some kind of non-degrading synthetic nerve that can be placed in the spine (or wherever) seems like a much better long term goal.
That sounds like a great idea for the long term, but what about the people that need a solution today? We have to make do with what we got until science advances.
Most DBS setups right now don't do any sensing. They just send a regular pulse that is manually adjusted. It doesn't really matter that much that there is a small amount of scar tissue around the electrode, the scar tissue is also a conductor. And, that area of the brain is likely pretty damaged anyway.
Sensing DBS with closed-loop feedback is very new. But there you're looking to sense at a totally different resolution. With something like a Utah array, they're looking to record extremely accurately from a very small number of neurons, like individual neurons. With DBS sensing they're looking to get the average response from somewhere between 1k-100k neurons. The scar tissue in the first case can overwhelm your signal, in the second case, it's a small fraction of the area you're recording from.
Makes you wish for a room temperature super conductor magnet that could deduce nerves from magnetic fields sensored and induce electric pulses via induction and wave intersection.
The brain will build up scar tissue around the electrodes and render them useless. These are basically little needles put into a jell-o which then wiggles around all the time. This constantly irritates and damages the tissue. Your immune system hates this.
Even within months there's a significant decay. But, within 5-10 years most of the array becomes pretty useless. Of course, you can't replace it easily. And the damage to that area, while local, isn't reversible.
There's a lot of research on trying to make a brain implant that can last longer so that all of these treatments become viable. But we still have basically nothing.