I'm looking for a word that refers, in biology, to a negative feedback loop similar to automatic gain control.
Equilibrium is the state reached when competing forces balance out to a steady state.
Homeostasis is what biological systems do to maintain a target state.
What is the English word that means what electrical engineers call "automatic gain control" (AGC)?
For example, one theory of the allergy epidemic has it that our immune system is tuned to protect us from pathogens, but we moderns live in "clean" environments without many pathogens, so the immune system starts reacting to harmless things instead (allergies).
The word would be used like this:
"One hypothesis explaining the allergy epidemic is that it is the result of [word]."
What is this called in biology?
An AGC circuit for example, raises the gain (for example of a microphone) until some level of signal appears.
I hope this question is clear.
[Edit: Googling, I see that some people use the term "risk homeostasis" (https://en.wikipedia.org/wiki/Risk_compensation#Risk_homeostasis) or "perverse homeostasis".
These are close, but "risk homeostasis" is specific to risk.
"Perverse homeostasis" is closer to what I'm looking for, but doesn't make clear what is perverse about it or that the mechanism involves seeking a level of reaction to a (perhaps non-existent) phenomenon.]
[Edit #2: Another phrase I see used is "closed-loop mechanism to generate a fixed response level". That's exactly right, but a terrible mouthful.
Do I need to coin a new word here? What should it be?]