Depression is a long period of negative thought patterns. The person is locked in a loop of insatisfaction, disappointment, health concerns, feelings of wasting life (guilt), followed by feelings of worthlessness. It is a terrible place to be. And unfortunately a lot of smart people fall into this mental trap. I am emerging from such an episode myself and I can relate perfectly to the article. I was helped by the book "Feeling good: The New mood therapy" and I highly recommend it to anyone who seeks help.