The death of Robin Williams hit me hard. Mr. Williams was a creative force and his untimely passing was apparently due to depression. Depression is a chemical state in the brain and if it becomes chronic requires treatment. Like any other physical illness serious problems, even death, can arise if it is not treated. I have faced that problem with new birds at the sanctuary many times. Depression among birds leads to stereotypic behavior (pacing, bar strobing, repetitive motions such as cocking the head and moving in defined circles).
Perhaps Mr. Williams would still be with us had he been treated for his depression. Depending on its severity there are several treatments that can be helpful including: exercise, diet, light therapy, wake therapy, meditation, and psychotherapeutic drugs (see wikipedia footnote).Please click on the link below for the full article in PDF format.