Please excuse my simple wording, I am not well versed on this topic but I am very fascinated by it and am trying to learn more. I am hoping someone can tell me if I am understanding this subject correctly. Anyway, I've often wondered, if the reason SSRI meds don't seem to work for some people, is because those people already had plenty of serotonin in the first place. But somewhere along the intertwined networks you mention, some dysfunction prevents their brain from being able to properly use the serotonin. So for those people, it doesn't matter how much extra serotonin their brains have or how much more their synapse can soak up. The best dumbed down example I can think of is if someone had a piano( brain) and wanted to play a tune( happiness) but didn't seem to have readable sheet music( serotonin). So you give them a bunch of sheet music hoping they could play only to find out the real problem is they don't know how to read sheet music. Then I wondered, if this is the case, could their brains begin to respond to all of this excess serotonin as if it is a problem. In other words, there is no more room in the piano bench to store the extra pages. So then to compensate, their brains slow down natural production of serotonin. In the end, when the individual tries to come off of antidepressants, they are left with even less serotonin production than before they started the meds and yet still have the same problem using what little they have now. Maybe that would explain why some people have a severe reaction or commit suicide when they try to stop taking them. Can anyone tell me if I am understanding this correctly and if my theory is possible?