People who listen to certain recordings of music are in danger of being unduly influenced by spoken messages that have been recorded backwards on the records or tapes. A consequence of the view above is that ['backwards messages can be added to a recording while still preserving all the musical qualities of the recorded performance', 'the recordings on which such messages appear are chosen for this purpose either because they are especially popular or because they induce a trancelike state', 'when people listen to recorded music, they pay full attention to the music as it plays', 'if such messages must be comprehended to exert influence, then people must be able to comprehend spoken messages recorded backwards']