"Determining the cause for negative motions" Sounds simple, but it aint. That requires careful study over along period of time and getting to know the subject

"Determining the cause for negative motions" Sounds simple, but it aint. That requires careful study over along period of time and getting to know the subject well, plus the history, and an understanding of the environment. What a person who is depressed is focusing on, can be unrelated to the deeper reason. If there ever is "a" truly deeper reason. More likely it is a set of / mesh of things that have built up. Lastly nobody can describe depression. Those who have lived and are living with severe clinical depression know what it feels like, (like myself), the rest, the doctors and scientists are guessing.