An update

Here is an update to my own "Depression Model." My avid readers will remember that I believe some forms of depression are fitness indicators like peacocks' tails (Please refer to my post on 9/8/07.) So as a cure, I have recommended that depression patients "live off the land." Here is a recent study:

http://www.nowpublic.com/health/playing-dirt-might-help-depression-soil-bacterium

My model successfully predicted such a benefit 1,5 YEARS BEFORE this study was published.

Another (not so recent) study suggests that sleep deprivation helps alleviate depression. Exercise, soil, sleep deprivation: Hardly an ancient tribal chief's troubles.