I have been thinking about a world where there have been incredible advancements in biotechnology. Genetic engineering, advanced bionics and, of course, the long-time human tradition of finding new and innovative ways to kill each other. One of these, is Mechs.
Mechs are useful for more than fighting, they're very useful in construction and farming, really anywhere where heavy lifting and long endurance tasks are required and the regular engineering of humans (be it genetic or machined) simply wont cut it. They have even found uses in space applications, like station maintenance or personal short distance transport. Think of them like Fallout power armor, Halo's spartan armor, or Javelins from Anthem, pictured below.
Of course, these kinds of tools are very useful with military applications. Mostly mercenaries who want to take on very risky and expensive contracts and missions and have the money to be fitted like a walking tank, but they have a lot of use cases in professional militaries too.
There is a massive problem with them, however. There is a strange medical condition that affects users of these mechs that seemingly has no root cause and is not at all understood. It tends to happen with more advanced mechs with more systems (such as more weapons and active defence systems)
Its a condition where people in the mechs start to believe they ARE the mech and are not humans driving them, believing themselves to be sentient AI or something. Users are nearly always incredibly paranoid about being disassembled or tampered with, and will usually fight anyone attempting to remove them from the mech or even get close due to the fear of being EMP'd or sneakily opened up. The condition is treatable simply by removing the person in the mech (simply might not be the best word for it, as they will be actively resisting this), and has no side effects after the fact other than being shaken up and potentially injured from the fight to remove them from the mech.
Currently IRL we have a lot of terms to describe all kinds of psychological issues. This would probably be called a "Persecutory delusional disorder" (people with this disorder IRL believe someone is attempting to harm them) but how would we specify that it is both acute and caused by using a mech?
What would the most medically accurate term be for describing this condition?