Forget AI, for me this is evoking visions of government-mind-control creepiness.

This is the more likely scenario.

Having a computer and radio in your brain doesn't mean you have to expose access to anything via the radio link. Even if you want to, there has to be software in between the connection to the meat and any APIs you provide for controlling your body, mapping intentions to raw signals for the neurons. This would have some form of access-control and safety features.

How will you know if the safety features have not been compromised?

By building it yourself.

Which'll be impossible. A single human isn't even capable of the supply chain for your average dumb toaster, let alone a neural implant.

> What's stopping a malevolent AI from controlling humans who are connected via neural lace?

Other than that they don't exist, you mean?

A general AI, especially a "malevolent" one, is such a mind-blowingly powerful entity that these questions are rather pointless. A self-improving GAI could rapidly take over the planet and have a myriad ways of "controlling humans".

I'd be far more concerned with other humans messing with it. And before that, just bugs and other damage.

Humans aren't good for much. Why expend energy controlling and sustaining what you can replace and outperform.