In 1993 Rauscher, Shaw and Ky published results of a study in which they measured the increase of spatial reasoning skills in 36 college students who listened to music composed by Mozart. The researchers reported increases of between 8 and 10 points on the IQ spatial reasoning task scale as opposed to those students who sat quietly for the 10 minute period or listened to relaxation tapes. The results of these findings were attributed to listening to the composer's sonata and resulted in coinage of the phrase 'The Mozart Effect.' Since these findings were first reported there has been a contentious debate as to the validity of the Mozart Effect.
According to Caulfield (1999) the original study was performed on college students, not infants, and the results were temporary. Rauscher et al. (1997), however, conducted a two-year study where they found that preschool children who took piano lessons had increased spatial reasoning skills. This led them to conclude that music exposure to young children enhances the development of the brain, particularly in the area of spatial reasoning skills. These findings led Caulfield (1999) to question at what age music can be processed and remembered by young infants. According to LaFuente et al (1997 as quoted in Caulfield, 1999) infants during their last trimester care capable of hearing music. He and his associates conducted a study in which they had pregnant women in their final trimester (40 weeks) play tapes of basic chords and gradually moving up to more complex musical patterns. Each mother completed between 50 and 90 hours of musical listening prior to delivery. The researchers found that during the first six months the infants "exhibited significantly more rapid development of many behaviors, including visual tracking, eye-hand coordination, facial imitation and babbling" (Caulfield, 1999, p. 120) but Caulfield warns that the mother's knowledge of the study may have been a confounder.
Nantais and Schellenberg (1999) explain that the Mozart effect is "similar to robust psychological phenomena such as transfer or priming" (p. 370) but the main difference is that the Mozart Effect, if in fact it exists, would be caused by passive listening as opposed to active doing. In an attempt to replicate the Mozart Effect the researchers selected 84 undergraduates, 56 for one experiment and 28 for a second. They used two different music pieces: the Mozart sonata and a piece composed by Schubert. Although their findings showed an improvement in spatial reasoning by both groups who listened to music as opposed to the control group who sat in silence, they concluded that the slight improvement was due to a positive stimulus versus a negative stimulus (music to