Description of participants
| Total sample | Main group mean age at MTP1: 8.6 years ± 9 months | AD(H)D group mean age at MTP1: 8.9 years ± 8 months | ||||||
|---|---|---|---|---|---|---|---|---|
| n = 111 (54 males, 57 females) | n = 21 (all males) | |||||||
| Longitudinal MRI sample | n = 102 (49 males, 53 females) | n = 21 | ||||||
| Longitudinal MEG sample | n = 102 (51 males, 51 females) | n = 20 | ||||||
| Type of musical training | Private + JeKi | Private only | JeKi only | None | Private + JeKi | Private only | JeKi only | None |
|---|---|---|---|---|---|---|---|---|
| Number of subjects | 38 | 38 | 16 | 19 | 5 | 4 | 2 | 10 |
| Age in months at MTP1 (years; months) | 104.1 ± 8.5 | 101.8 ± 10.7 | 104.4 ± 8.5 | 97.8 ± 7.1 | 100.6 ± 4.7 | 108 ± 6.9 | 116 ± 5.6 | 103.9 ± 8.5 |
| (8; 8) | (8; 6) | (8; 8) | (8; 2) | (8; 5) | (9; 0) | (9; 8) | (8; 8) | |
| Musical starting age (years; months) | 85.5 ± 12.9 | 71.8 ± 14.7 | 95.3 ± 8.6 | 94.6 ± 4.7 | 90 ± 18.5 | 92 ± 5.7 | ||
| (7; 2) | (6; 0) | (7; 11) | (7; 11) | (7; 6) | (7; 8) | |||
| Private IMP at MTP1 | 1.9 ± 2.8 | 5.8 ± 5.6 | 0.35 ± 0.2 | 2.25 ± 2.6 | ||||
| JeKi IMP at MTP1 | 0.7 ± 1.3 | 0.4 ± 0.5 | 0.05 ± 0.1 | 1 ± 0 | ||||
| (Total) IMP at MTP1 | 2.6 ± 3.5 | 5.8 ± 5.6 | 0.4 ± 0.5 | 0.4 ± 0.3 | 2.25 ± 2.6 | 1 ± 0 | ||
| Private IMP at MTP2 | 2.5 ± 3.0 | 8.3 ± 6.5 | 1.0 ± 0.8 | 4.5 ± 4.0 | ||||
| JeKi IMP at MTP2 | 1.7 ± 1.8 | 1.4 ± 0.8 | 0.6 ± 0.1 | 1.5 ± 0.01 | ||||
| (Total) IMP at MTP2 | 4.2 ± 4.2 | 8.3 ± 6.5 | 1.4 ± 0.8 | 1.6 ± 0.8 | 4.5 ± 4.0 | 1.5 ± 0.01 |
Both the main group and the AD(H)D group included children with and without musical experience but in different proportions. The children were musically trained in extracurricular private lessons, the JeKi program offered at school, or both. IMPs are separately listed for the JeKi-related and private training at MTP1 and MTP2. If not stated otherwise in the text, IMP is the total accumulated practice (JeKi + private) at MTP2. All means and SDs are based on the total sample and not on the slightly reduced samples of the longitudinal MRI and MEG analyses.