One of my favorite facts about neural interfaces... all electronics use negative charges for communications. But neurons use positive charge in the form of calcium flow. This makes it really hard to bridge that difference.
I wonder why is it so, in the end it's just electrons flowing from negative to positive end to create current, why do they behave differently inside neurons?
It’s because the flow of electrons driving current is mostly used only in one part of neurons: mitochondria. It’s used to generate ATP, which is the actual currency of energy in cells. This in turn powers systems that send and receive ions that are generally positively charged (why this is, I’m not sure) for neural communication.
So, while reading electrical signals is possible, returning them is tough because you’re so far removed from the language of the neurons when using electrons.
