1. I've sat in on multiple psych conferences. If you compare them with conferences in other specialties, you'll soon realize that there is a severe lack of scientific discourse happening. As I said, there is a belief that the field is an art and that the practitioners within are artists who rely heavily on their experience and preferences. Literature is hardly discussed. The DSM is the bible.

2. Yes, the best and most practical test we have is an EEG that, at best, tells you that something wonky is going on in this vague region of the brain. Good for seizure disorders, little else. The other tests we can run are to detect physiological causes of psychiatric symptoms external to the brain, like thyroid disorder, uremia, overdose, etc. Nobody sends a patient down for a routine fMRI. What tests are you referring to?

3. I'm not advocating to wait until we've achieved a complete understanding of the brain, but rather we explore more conservative managements while we get a better understanding of the mechanical workings on the brain. CBT, DBT, psychotherapy, etc, should be actively encouraged by psychiatrists as first-line options for many of these conditions. They simply aren't.