The possible health benefits of the music of Mozart have been assessed in the April 2001 edition of the Journal of the Royal Society of Medicine. There has been controversy about the benefits ever since researchers claimed that listening to the K448 piano sonata improved spatial reasoning skills. Later research suggested that K448 can reduce the number of seizures in people with epilepsy. Professor John Jenkins assesses international evidence on the effect of music on the brain, and calls for more work to be done to discover the key ingredient in the "Mozart Effect". The original “Mozart effect” study in 1993 assessed volunteers’ spatial reasoning after listening to sonata K448, relaxation tapes or silence. Results suggested that just 10 minutes of Mozart’s music improved their performance of tasks such as paper-cutting and folding. Later studies found that rats negotiated a maze faster after hearing K448 than rats who were played white noise, silence, or minimalist music. Elsewhere, children taught a keyboard instrument for six months, learning simple melodies (including Mozart), did better on spatial-temporal tests than children who spent the time working with computers. Controversy arose when other researchers could not reproduce the positive results. Scans have shown that the human brain uses a wide distribution of areas to listen to music. Rhythm and pitch tend to be processed in the left side, timbre and melody on the right. Those parts of the brain which we use for spatial/temporal tasks actually overlap with the music processing parts. Professor Jenkins suggests that “listening to music would prime the activation of those areas of the brain which are concerned with spatial reasoning”. More recent work with epilepsy patients has indicated what Professor Jenkins calls “a more impressive indication of a Mozart effect”. Once again, sonata K448 was played to participants, most of whom showed a decrease in their epileptiform activity - the patterns in the brain that produce epileptic seizures. Computer analysis of pieces by various composers showed that the music of Mozart and Bach shared a common factor, a high degree of ‘long-term periodicity’, in other words, wave forms repeated regularly, but not very close together, throughout the piece of music. By contrast, music which had no effect on either spatial reasoning or on epileptic seizures did not have this factor. Professor Jenkins commented: "It is suggested that music with a high degree of long-term periodicity... would resonate within the brain to decrease seizure activity and to enhance spatial-temporal performance”. Professor Jenkins concludes that any health benefits of listening to music are “not specific to Mozart’s compositions”, and calls for more research to be done on music other than K448, with longer listening times. For the benefits to be of real use, we need to discover exactly what musical criteria have to be present for the “Mozart effect” to take place. Apart from another Mozart Concerto, K488, only one other piece of music has been found to have a similar effect, a song by the Greek-American compositor Yanni. Entitled 'Acroyali/Standing In Motion', it is featured on his album "Live At The Acropolis". This composition was chosen by researchers because it was similar to Mozart's K448 in tempo, structure, melodic and harmonic consonance and predictability.