Short-term second language and music training induces lasting functional brain changes in early childhood

Abstract

Immediate and lasting effects of music or second-language training were examined in early childhood using event-related potentials. Event-related potentials were recorded for French vowels and musical notes in a passive oddball paradigm in thirty-six 4- to 6-year-old children who received either French or music training. Following training, both groups showed enhanced late discriminative negativity (LDN) in their trained condition (music group-musical notes; French group-French vowels) and reduced LDN in the untrained condition. These changes reflect improved processing of relevant (trained) sounds, and an increased capacity to suppress irrelevant (untrained) sounds. After 1 year, training-induced brain changes persisted and new hemispheric changes appeared. Such results provide evidence for the lasting benefit of early intervention in young children.

Figure 1

Training effect in the vowel (a, b, left panel) and note (c, d, right panel) conditions. (a, c) Difference wave (i.e., deviant – standard) at Fz (as a representative electrode) is shown for each group (n = 18 each). (b, d) LDN change (i.e., pre – post in each group) was averaged across six frontal electrodes (AF3, AFz, AF4, F1, Fz, F2) in the latency window of 650–850 ms for (b) the vowel condition and 450–650 ms for (d) the note condition. The trained group showed enhanced LDN to the trained sound (French group-vowel; music group-note), whereas the untrained group showed decreased LDN to the untrained sound (French group-note, music group-vowel). Error bars = s.e.m.

Figure 2

Lasting training effects after one year. (a) Vowel condition. Difference wave (i.e., deviant – standard) at F3 and F4 (as representative electrodes for left and right, respectively) are shown for each group in the post and follow-up sessions (n = 16 in French group, n = 14 in music group). At follow-up (latency window 475–600 ms), the French group showed enhanced LDN on the left compared to right, and the music group showed enhanced LDN on the right compared to left (also see Fig. 3). (b) Note condition. Difference wave at Fz (as a representative electrode) is shown for each group across three testing sessions (n = 16 in French, n = 14 in music). At follow-up (latency window 450–600 ms), the music group maintained LDN to the musical sound (albeit reduced), whereas the French group showed LDN similar to that of the pretest. Error bars = s.e.m.

Figure 3

Laterality effects in the vowel condition at one year follow-up. LDN change from pre (i.e., pre – follow-up in each group) was averaged across two left (F3, F5) and two right (F4, F6) electrodes in the latency window of 475–600 ms. The French group (n = 16) showed enhanced LDN to the vowel sounds on the left electrodes at follow-up session, whereas the music group (n = 14) showed increased LDN to the vowel sound on the right frontal sites at follow-up. Note that pre – post was not plotted as the laterality effects were not observed at post-test. Error bars = s.e.m. FU = follow-up, L = left, R = right.

Figure 4

Lasting effects in the note condition at one year follow-up. LDN change (i.e., pre – post, or pre – follow-up in each group) was averaged across six frontal electrodes (AF3, AFz, AF4, F1, Fz, F2) in the latency window of 450–600 ms. Note that values are slightly different from Figure 1d because the latency window for Figure 1d was longer (450–650 ms). The graphs illustrate different patterns of LDN change observed in the two training groups: the trained group (music on the right) maintained LDN to the trained sound at follow-up (albeit reduced), whereas the untrained group (French on the left) showed LDN returned to baseline at pre. Error bars= s.e.m.