Both auditory and visual messages in historical works of art are a source of intrigue for modern art historians. For example, subliminal messages left in Leonardo da Vinci's "The Last Supper" was a theme in Dan Brown's best-selling novel, "The Da Vinci Code." The fictional novel purported that messages recorded inside Da Vinci's masterpiece pay homage to a side of Christianity long forgotten. Assigning the effeminate image of John the Apostle, seated next to Jesus, as Mary Magdalene. But this summation has never been corroborated by art historians. However, in 2010 a secret message was discovered in the eyes of the Mona Lisa. Two sets of letters are visible with a magnifying glass, "LV" and "CE," or possibly "B." The letters were revealed after experts found an antique book that referenced their existence.
Auditory messages could be responsible for the success of the British Broadcasting Company, or BBC. When the radio was first introduced to the British public, many people mistrusted the technology of the machine. The BBC wanted to convince listeners to stay tuned in, so they added a backward message into innocuous jingles to help reassure the public. The message, "This is not a noose, no really its not," can be heard when the jingle is played backward.
The film industry is notorious for adding subliminal messages inside of animated films. The quick exchange of frames makes messages difficult to catch because they only last for a second. Many of these messages are sexual in nature and may originally have been intended as jokes by the animation team. For example, an animator for Disney's animated film "The Rescuers," released in 1977, added the figure of a nude woman in a background window.
Advertisers use both visual and auditory subliminal messages. Obvious messages sometimes result in an ad being pulled due to indecency. An ad for a flooring company that ran in the British Yellow Pages was pulled when someone discovered a surprising image when the ad was viewed upside down. In 1974 complaints about subliminal messages in advertising led the Federal Communications Commission, or FCC, to release a public notice stating the FCC's official position on the use of subliminal messages in television and radio advertising. The FCC believes that the use of subliminal messages is deceptive and in conflict with a licensed broadcast company's duty to serve the public, but the only regulations governing the use of subliminal messages are geared toward the alcohol industry.
Backward messages in popular music became a sensation in the 1960s when a message discovered on a Beatles song hinted that Paul McCartney had died. Other backward messages used by bands were less sinister. Credence Clearwater Revival's message to a woman, "I believe in my cool woman," is an example of a positive subliminal message.
The power of subliminal messages is thought by some to have life and death consequences. The band Judas Priest was sued by the family of two boys who committed suicide because of a subliminal message saying "do it" inserted in the song "Better By You, Better Than Me." Judas Priest won the case because no scientific evidence exists connecting subliminal messages with direct mind control.