People suffering from depression may actually have a more accurate perception of reality than those with healthy minds. This proposition is called Depressive Realism.
People suffering borderline or moderate depression more accurately interpret reality.
There are so many people that suffer from depression (and even have suicidal thoughts) because Avatar isn’t real and they can never go to Pandora, that there is a forum to help these people cope with this depression.
Sleep deprivation can cure depression.
Depression is likely an evolutionary adaptation that enables people to deeply analyze complex problems.
Chickens can suffer from depression.