I used to have the same view of where emotions come from. But after getting brain snapshots and diagnoses from medical doctors and a psychologist, I had to confront my personal history and conclude that habits of thought were only part of the solution. Hence the research findings that talk therapies and meds are more effective than either alone. (Not to mention that an effective therapy is one that produces a 30% solid success rate balanced with a %30 negligable response. Not something you want to hear if you're looking for magic pills to make your problems disappear.)

Anyway, as famed neuroscientist Ted Nelson once put it, "Everything is intertwingled." Just a couple of months ago I read an item about a rodent memory experiment in Helsinki that supported the theory that the reason antianxiety drugs work is that they stimulate neuroplasticity. The results would seem to explain why those drugs could show up in our bloodstreams within hours and yet take weeks for real results to show up -- and it also supports two-pronged approaches to improvement.