Just been having a bit of a Google on Hallucinogens and depression:
Found this from 2014 from the same people who conducted the study above http://edition.cnn.com/2014/09/17/he...al-depression/
Thought these were interesting too:
http://www.medicaldaily.com/depresse...ahuasca-328944
http://www.healthafter50.com/reports...ty/3635-1.html
It seems to be something that has been looked at for some time but has been hindered by the outlawing of hallucinogens due to their recreational usage.