This is a more splendid subgroup of the "lol" text message phenomena. It directly means "Holy Fuck That Was Funny" and actually triggers 17X the number of neurons in the brain while typing compared to "lol."

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.