THE NEUROSCIENCES AND MUSIC II I—DISORDERS AND PLASTICITY Effects of Musical Training on Key and Harmony

Even adults with no formal music lessons have implicit musical knowledge acquired through exposure to the music of their culture. Two of these abilities are knowledge of key membership (which notes belong in a key) and harmony (chord progressions). Studies to date suggest that perception of harmony emerges around 5–6 years of age. Using simple tasks, we found that formal music training influences key and harmony perception in 3- to 6-year-olds, and that even nonmusicians as young as 3 years have some knowledge of key membership and harmony. Key words: music; key membership; harmony; tonality; pitch; musical education Sensitivity to some musical aspects appears in infancy,1 suggesting constraints of the auditory system or information-processing biases. How-ever, other aspects depend on exposure to a particular musical system. Notable experience-dependent aspects are key membership (which notes do and do not belong in a key) and percep-tion of harmony (likelihood of sequential and simultaneous note combinations). Even adults with no musical training have implicit knowl-edge of key and harmony,2,3 suggesting that these skills develop through mere exposure. Key membership and harmony perception are acquired relatively late.4 Trehub and col-leagues5 found that 4- and 5-year-olds could more easily detect a change in a melody if its notes belonged to a key than when they did not, in contrast to infants, who could detect both changes with equal ease. Similarly, Trainor and Trehub2,3 found that 5-year-olds, 7-year-olds, and adults detected a deviant out-of-key note better than a deviant in-key note, while infants detected these equally well. Thus, it appear