There is some evidence that suggests that the human brain can decode a recorded message that is played backwards, even though the person isn't consciously aware of what's being said. On the Beatles 'White' Album (called "The Beatles"), there is a song called "No. 9 Revolution." In one segment, John Lennon chants "number nine, number nine," which, when played in reverse, says "turn me on dead man."
This fueled rumors that group member Paul McCartney was dead. Eric Nehart, of Mechanicsburg, PA, who does research into subliminal techniques used in rock music, said that someone he knew, who was listening to "No. 9 Revolution", and hallucinating from drugs, was imagining that there were no windows or doors in the room, and that fire was coming at him. He began to scream, "Let me out, let me out." A section of the song, when played in reverse, says: "Let me out."
On the Electric Light Orchestra's album "Face the Music", there's a song called "Fire on High", a segment of which, when played in reverse, says: "The music is reversible, but time isn't, turn back, turn back, turn back..." In their album "Eldorado", there are backward messages which say: "Christ you're the nasty one, you're infernal," and "He's there on the cross and dead." Queen's song, "Another One Bites the Dust," when played in reverse, continually says: "It's fun to smoke marijuana."
In Jefferson Starship's "Blows Against the Empire", the song says: "I've got a surprise for you, a child is coming, a child is coming. Everything's gonna get better, it's gonna be brighter." When played in reverse, it continually says: "Son of Satan." On the live album of Black Oak Arkansas, called "Raunch and Roll", during the song, "The Day Electricity Came to Arkansas" the lead singer Jim Landy utters something unintelligible, then laughs. When it is played backwards, he says: "Satan, Satan, Satan; He is God, he is God, he is God." Some researchers believe that not all of this is intentional, that some of it may be put there supernaturally.