Where musical ability comes from

Introduction: Researchers studied twins to see how much genes contribute to musical ability, and whether practice explains differences between people who share the same genes.

Participants: 2,400 adult twins (1,200 pairs: 520 identical pairs and 680 fraternal pairs) aged 27 to 54, drawn from a national twin registry in northern Europe. Of the participants, 58% were women. Race/ethnicity was not reported.

Method: Identical twins share all of their genes, while fraternal twins share about half, like other brothers and sisters. Each twin took an online musical aptitude test, separately from their co-twin, that measured how accurately they could tell whether two short melodies, rhythms or pitches were the same or different (scored 0 to 100). Each twin also estimated the total hours they had spent practicing an instrument or singing over their lifetime.

Results and Discussion: Identical twins' aptitude scores were more similar to each other (r = +0.60) than fraternal twins' scores were (r = +0.32). Across all participants, more hours of practice went with higher aptitude scores (r = +0.30). However, in the 64 identical pairs in which one twin had practiced at least 1,000 hours more than the other, the twin who practiced more did not score significantly higher on the aptitude test (mean difference = 0.4 points).

Introduction: Researchers studied children who were adopted as babies to compare the influence of the families children are born into with the families that raise them.

Participants: 132 children in the United States and Canada who had been adopted before 6 months of age, and their adoptive parents. The children were 12 years old when tested, and 49% were girls. Agency records describing the birth mother's musical background were available for 95 of the children. Race/ethnicity was not reported.

Method: Adoptive parents reported how often music was part of family life (for example, singing together, instruments in the home, concerts and music lessons), producing a home music score from 0 to 30. Each child took a pitch and rhythm discrimination test (scored 0 to 100). For the 95 children with records, researchers coded the birth mother's years of musical training.

Results and Discussion: Children's test scores were positively correlated with their adoptive family's home music score (r = +0.41). Among the 95 children with records, scores were also positively correlated with their birth mother's years of musical training (r = +0.24), a weaker but statistically significant relationship. Children from homes in the top quarter of home music scores averaged 71 on the test, compared with 58 for children from homes in the bottom quarter.

Introduction: Researchers tested whether learning to play an instrument in later adulthood changes the brain.

Participants: Sixty adults aged 55 to 75 (mean age = 64; 35 women and 25 men) with no previous musical training, recruited through community centers in a large city in Spain. Race/ethnicity was not reported.

Method: Participants were randomly assigned to 6 months of piano lessons (one hour per week, plus about 3 hours of practice at home each week) or to a waitlist group that received lessons after the study ended. Before and after the 6 months, all participants took a melody discrimination test (scored 0 to 100) and had an MRI scan measuring the volume of gray matter, brain tissue rich in neuron cell bodies.

Results and Discussion: The piano group's mean melody discrimination score rose from 61 to 74, while the waitlist group's rose from 60 to 62. The piano group also showed significant increases in gray matter in the brain region that controls finger and hand movements and in regions on the sides of the brain that process sound. The waitlist group showed no significant brain changes. Participants who practiced more at home showed the largest increases.