Keep in mind that we also have no clue how general anesthesia works! It's not just psychiatry, many medications targeting the nervous system (e.g. muscle relaxants) have unknown mechanisms of action https://en.wikipedia.org/wiki/Category:Drugs_with_unknown_me...
I think you're being extremely reductive about what neuropsychiatry actually entails.
I think you're being extremely reductive about what neuropsychiatry actually entails.