Analysis of the music tasks showed greater improvement over the year in melody, harmony and rhythm processing in the children studying music compared to those not studying music. General memory capacity also improved more in the children studying music than in those not studying music.
Link to Science Daily article
Link to abstract in Brain
Full article in Brain
The study in Brain only used kids in Suzuki programs in the "Toronto area", rather than kids in a broad-based spectrum of musical programs in a wider geographical region. Does this study merely prove that there is a high level of Suzuki instruction in Toronto?
In addition, it appears that only 12 children were tested, 6 in Suzuki programs and 6 not, hardly a sizable number of test subjects to be a definitive study.