The Mozart Effect is the theory that listening to Mozart music increases spatial-temporal reasoning, and for children under the age of 3 years old, increases brain development.
In 1993, Gordon Shaw and Frances Rauscher tested 36 college students at the University of California, Irvine. The students' spatial-temporal reasoning skills were tested before and after listening to 10 minutes of the Mozart Sonata for Two Pianos in D Major. The results for the Standford-Binet IQ test that the students took were slightly higher after the Mozart music than before.
All of the attempts to duplicate the test results have failed. They were completely unnecessary, of course, as one unchecked scientific experiment is enough to start a frenzy. The media loves this kind of "scientific" stuff, and took every opportunity to feed it to the public as proven fact. The public doesn't need to see the test results, as long as they hear the word "scientific", they're satisfied. Everyone else looking for an easy buck joined in, and now you can buy dozens of books and special Mozart CDs in order to assure yourself that your child will be the next Stephen Hawking. The governors of Tennessee and Georgia have created programs dedicated to giving Mozart CDs to newborn children.
To quote Frances Rauscher, who co-authored the original study:
"I'm horrified and very surprised over what has happened. It's a very giant leap to think that if music has a short-term effect on college students that it will produce smarter children. When we published the study results, we didn't think anyone would care. The whole thing has really gotten out of hand."
She also agrees that playing Mozart to infants will not raise IQs (something that wasn't claimed in the 1993 study in the first place). Her partner, Gordon Shaw, followed a different path, and released a book and CD set named "Keeping Mozart in Mind".
One way or another, introducing children, or even adults to Mozart can't be considered a bad thing, per se. And music, including Mozart, can positively change your mood . But it's not going to turn you into Einstein, or make you pass the test you didn't study for. The Mozart Effect is just an example of how the media and rumor can unknowingly encourage pseudoscience.
And we'll all believe it, because it's interesting.