I think that we're banking very much on brain imaging. The reason is that the symptom expression in depression or post-traumatic stress disorder, among other mental illnesses, is very variable. We need to better understand the genesis. Where are those circuits in the brain that are responsible for the expression of these symptoms? When we find out, we can go to the source of where things are going awry, understanding the neurochemical processes that are making the circuits go rogue. Then we can fix them. Unless you can see and identify them, you cannot find ways to fix them.
On May 5th, 2016. See this statement in context.