Western Sydney University, Australia; MARCS Institute for Brain, Behaviour and Development, Australia.
Western Sydney University, Australia; School of Psychology, Western Sydney University, Australia.
Dev Cogn Neurosci. 2021 Apr;48:100923. doi: 10.1016/j.dcn.2021.100923. Epub 2021 Jan 21.
Social interactions are vital for healthy brain development. Burgeoning behavioural evidence indicates that a caregiver who provides contingently timed vocal responses to infant vocalisations provides key support for early language development. Understanding how contingently timed vocal responses relate to neurodevelopment in early infancy is lacking. This study compares event-related potentials (ERPs) to contingent and non-contingently timed vocalisations in 6- and 9-month-old infants (n = 36), and adults (n = 24). ERPs were recorded from each age group while listening to a naturalistic 21-minute recording of a mother playing and conversing with her baby. At 6-months, infants showed a significant positive ERP response to contingent vocalisations by the mother and infant. At 9-months infants showed negative ERP response to the mother's contingent speech. Adults showed no differences in ERPs between contingent and non-contingent speech regardless of the talker. We interpret the increased positivity in response to contingent speech as suggesting that infants show an attentional response at 6-months, and the increased negativity at 9-months relates to lexical-semantic processing. Further work is necessary to confirm the development of distinct ERPs shown in response to natural speech.
社交互动对大脑健康发育至关重要。越来越多的行为证据表明，对婴儿发声做出及时回应的照顾者为早期语言发展提供了关键支持。然而，对于及时回应的发声如何与婴儿早期的神经发育相关，我们知之甚少。本研究比较了 6 个月和 9 个月大的婴儿（n=36）和成人（n=24）对及时和非及时发声的事件相关电位（ERPs）。在每个年龄组中，通过记录他们在聆听母亲与婴儿玩耍和对话的自然 21 分钟录音时的 ERPs。在 6 个月大时，婴儿对母亲和婴儿的及时发声表现出显著的正 ERPs 反应。在 9 个月大时，婴儿对母亲的及时言语表现出负 ERPs 反应。无论说话者如何，成年人在及时和非及时言语之间的 ERPs 没有差异。我们将对及时言语的反应中增加的正性解释为婴儿在 6 个月大时表现出注意力反应，而在 9 个月大时增加的负性反应与词汇语义处理有关。需要进一步的工作来确认对自然言语反应中表现出的不同 ERPs 的发展。
