A cyborg is a cyborg. You do not get to make up a definition in order to limit the discusion of it.
Where legal definitions are concerned, neither do you. And it still doesn't matter. Current law covers it without even stretching.
I purposely created a fictional scenarii in order to
Change the subject, and not answer the real point: current law covers implanted technology in one of two ways, and does so quite thoroughly.
exempt bias but if you do not think it is theoreticaly possible, i suggest you pay more attention. They are recording brain waves as we speak in order to make prosthetics as transparent as possible. If they can relay and replay those signal to prothetics, it isn't unimaginable that it could be done for the real thing. And yes, science fiction has already done it.
Interpreting the equivalent of a mouse signal and replaying memories are not even qualitatively the same thing, and we have already proven, quite conclusively, how inaccurate memory can be, even of one's own actions. The chances of such a system being reliable enough to be admissible are zero within the lifetimes of anyone alive today. And even if such technology were developed, current law still covers it.
Once again, and I'll use small words this time:
Either it is an electronic device, and the laws covering the search of computers and cell phones covers it - show probably cause and you get a warrant.
Or it's part of the body, and decades old case law covering forced collection of biometric evidence - DNA, fingerprints, blood samples - covers it. Show probably cause, and you get a warrant.
There's no difference, legally.