Scientists have discovered that music training has significant influences on the brain development of young children leading to improved memory over the course of a year. The fact that musical training changes the way the brain reacts to music might not be very surprising, but researchers also found that the musically trained children performed better in a memory test that is correlated with other skills such as literacy, verbal memory, visiospatial processing, mathematics and intelligence.

The team led by Dr Laurel Trainor, professor of psychology, neuroscience and behavior at McMaster University, Canada, and Director of the McMaster Institute for Music and the Mind, have measured over the course of one year the changes in brain responses to sounds in children aged between four and six.

"This is the first study to show that brain responses in young, musically trained and untrained children change differently over the course of a year," said Trainor. "These changes are likely to be related to the cognitive benefit that is seen with musical training."

Other studies have shown that older children taking music lessons show greater improvements in IQ scores than children taking drama lessons.

"Previous work has shown assignment to musical training is associated with improvements in IQ in school-aged children," said co-author Dr Takako Fujioka from Baycrest's Rotman Research Institute. "Our work explores how musical training affects the way in which the brain develops. It is clear that music is good for children's cognitive development and that music should be part of the pre-school and primary school curriculum."

When the study began, six of the children (five boys, one girl) had just started to attend a Suzuki music school while the other six children (four boys, two girls) had no music lessons outside school. Researchers choose children trained by the Suzuki method because it ensured they were all trained in the same way. Other musical schools train the children either according to their initial musical talent or to their families' wishes. Moreover, as the children were just starting their musical training, the Suzuki method provided a good model of how training in auditory, sensory and motor activities induces changes in the cortex of the brain.

The research team investigated how auditory responses in children matured over the period of a year, whether responses to meaningful sounds, such as musical tones, matured differently than responses to noises, and how musical training affected normal brain development in young children. They monitored the brain activity while the children listened to two types of sounds: a violin tone and a white noise burst.

Researchers used non-invasive brain scanning technology called magnetoencephalography (MEG) which measures the small magnetic fields outside the head. The ionic currents of individual neurons are much too small to produce measurable magnetic fields, but when the neurons fire in groups, synchronized to each other, they do produce a small measurable magnetic field. Approximately 50,000 active neurons are needed for a detectable magnetic signal (the brain has around 100 billion neurons).

The main advantage of the MEG technique is its speed: it offers the possibility of measuring the brain activity almost in real time, millisecond-by-millisecond. This allowed the scientists to observe how the brain works as the auditory information gets from ears to different parts of the brain in a series of stages.

The team monitored the children four times during the year. During the first and fourth session, the children completed a music test (in which they were asked to discriminate between same and different harmonies, rhythms and melodies) and a digit span memory test (in which they had to listen to a series of numbers, remember them and repeat them back to the experimenter).

The MEG showed that all children had larger responses to violin tones than to noises and that over the course of the year, the time needed for the response to appear had decreased - as they matured, their brains got better at processing meaningful sounds. However, the tests showed that the Suzuki children experienced a greater change.

What's interesting is that this change was not strictly restricted to musical abilities, such as harmony and rhythm processing, but also affected the memory in general. The children who studied music scored better at the general memory tests.

"That the children studying music for a year improved in musical listening skills more than children not studying music is perhaps not very surprising," Prof Trainor said. "On the other hand, it is very interesting that the children taking music lessons improved more over the year on general memory skills that are correlated with non-musical abilities such as literacy, verbal memory, visiospatial processing, mathematics and IQ than did the children not taking lessons. The finding of very rapid maturation of the N250m component to violin sounds in children taking music lessons fits with their large improvement on the memory test. It suggests that musical training is having an effect on how the brain gets wired for general cognitive functioning related to memory and attention."

The team now plans to study whether musical training benefits older adults as well.