Peter Varghese, Kalashnikova Marina, Santos Aimee, Burnham Denis
MARCS Institute for Brain, Behaviour and Development, Western Sydney University, Penrith, Australia.
Sci Rep. 2016 Sep 28;6:34273. doi: 10.1038/srep34273.
Infant directed speech (IDS), the speech register adults use when talking to infants, has been shown to have positive effects on attracting infants' attention, language learning, and emotional communication. Here event related potentials (ERPs) are used to investigate the neural coding of IDS and ADS (adult directed speech) as well as their discrimination by both infants and adults. Two instances of the vowel /i/, one extracted from ADS and one from IDS, were presented to 9-month-old infants and adults in two oddball conditions: ADS standard/IDS deviant and IDS standard/ADS deviant. In Experiment 1 with adults, the obligatory ERPs that code acoustic information were different for ADS and IDS; and discrimination, indexed by mismatch negativity (MMN) responses, showed that IDS and ADS deviants were discriminated equally well; although, the P3a response was larger for IDS suggesting it captured adults' attention more than did ADS. In infants the obligatory responses did not differ for IDS and ADS, but for discrimination, while IDS deviants generated both a slow-positive mismatch response (MMR) as well as an adult-like MMN, the ADS deviants generated only an MMR. The presence of a mature adult-like MMN suggests that the IDS stimulus is easier to discriminate for infants.
婴儿指向性言语（IDS），即成年人在与婴儿交谈时使用的言语形式，已被证明在吸引婴儿注意力、语言学习和情感交流方面具有积极作用。在此，事件相关电位（ERP）被用于研究IDS和成人指向性言语（ADS）的神经编码，以及婴儿和成人对它们的辨别。从ADS和IDS中分别提取的两个元音/i/的实例，在两种异常刺激条件下呈现给9个月大的婴儿和成年人：ADS标准/IDS偏差和IDS标准/ADS偏差。在针对成年人的实验1中，编码声学信息的必需ERP在ADS和IDS之间存在差异；以失配负波（MMN）反应为指标的辨别结果表明，IDS和ADS偏差的辨别效果相当；尽管如此，IDS的P3a反应更大，这表明它比ADS更能吸引成年人的注意力。在婴儿中，IDS和ADS的必需反应没有差异，但在辨别方面，虽然IDS偏差产生了一个缓慢的正性失配反应（MMR）以及类似成人的MMN，但ADS偏差只产生了一个MMR。类似成人的成熟MMN的存在表明，IDS刺激对婴儿来说更容易辨别。
