I see, my intuition is that the brain is like a very complex analog amplifying station with different types of transistors, capacitors, resistors, whatever.
Drug A decreases 100ohm resistor values to 50 in a noise filter stage and "fixes" your problem with the radio.
Drug B has same 100ohm -> 50ohm effect, but in a different section of the radio and doesn't work.
Drug C increases the speaker resistance from 5ohm -> 10ohm and "fixes" your problem because you simply cannot hear the noise.
Drug D increases the microphone resistance from 5ohm -> 10ohm and the noise simply is not picked up.
Drugs A and B work the same way, drug C and D work the same way, but opposite to how drugs A and B work and they all provide the same net effect as far as I'm concerned.
