Michael Good point about the referenced character.
As for neural interface (notice no caps, as it is not a discreet item per se), it is definitely defined. Brought up the core book on my phone to double check, thank you very much
"Besides their wireless functionality, almost all cyberware devices are equipped with a neural interface (not to be confused with DNI) that lets you mentally activate and control their functions. You can use this in place of wireless control, preventing wireless hacking, as long as all of the “moving parts” are connected to your nervous system. An item that has a wireless bonus, however, can only gain that full level of functionality if wireless functionality is active."
As I read this, you can run most cyberware without having it wirelessly enabled (a smartlink wouldn't need to be wireless if the character had an implanted commlink, for example, as the two could communicate directly through this neural interface), but wireless bonuses only apply if the item has wireless on.