art is personal not cultural :)
and how do u knw that none of us never painted? may be few of us r artists? who knows :)
and many ppl who seem what they r r actually nto what they r. so it really doesnt prove anything . these masks that we ppl wear as our faces r really mind boggling trust me :)
what u see as mentally sick and derprives many think of it as bold and free. so we really cant judge any1 and we shudnt.
art is nor just personal or cultural...its a form of expression and it can be both at the same time. you can even politicize them.
we are the ones who are questioned about their art that when they can paint nude, why dont u?
well its a long discussion behind their sick and deprived practices.