Sky, could you be a little more descriptive.
There seems to be information about microwave devices that can put voices directly into someones head, possibly causing symptoms simular to schizophrenia in the target victim or possibly even to include "Beautiful Mind" concept but without the visuals.
Instead of wanting to know particulars, I would jump to the bottom line, ask who would want such a device, for what reason and who would have such a device, then work backwards from there if it is at all necessary after determining the answer to those previous questions.