The link between sequence and language processing in the adolescent brain

这项工作解决了听觉技能和语言能力之间的联系。听觉能力对正常的语言习得是必不可少的：这里讨论的是语言发展是否需要听觉模式分析的特殊技能。许多研究已经检验了分析单个语音或语音对中的简单语音模式与语言技能的相关性。我们感兴趣的是，是否更复杂的声音序列的分析是特别相关的语言技能。这是有价值的，因为听众需要将语音流分割成正确的语音单元，然后才能正确地理解这些单元。我们提出的假设，序列分析的基础上，一些不同的线索是至关重要的语音理解：序列的音高像旋律，序列的时间间隔像节奏和序列的音色或“音色”。序列分析需要在听觉大脑（包括听觉皮层）中进行高水平的分析，并在青春期继续发展。我们建议研究的听觉分析和语言技能之间的联系，在早期和晚期的青春期检查的假设，根据我们以前的工作（在青春期早期），不同类型的序列分析是重要的，在不同阶段的青春期。以节奏为例，在早期青少年中，对简单规则节奏（如节拍器）的分析与语言之间存在关系，而在年龄较大的受试者中，这种关系与更抽象的节奏有关，如要求受试者“找到节拍”。这项工作很重要，因为许多受试者无法通过正常的听力来习得语言。有证据表明，这一过程在诵读困难症中出错，诵读困难症被定义为一种阅读和拼写障碍，不能用智力低下或缺乏机会来解释。阅读障碍发生在5%的人口中，给个人造成终身问题，给社会造成巨大损失。如果我们证明听觉序列分析和语言技能之间存在关键联系，这将表明基于听觉序列训练的新的行为干预措施有助于语言。这也表明，为了理解发育性语言障碍，需要进一步研究负责序列分析的大脑部分。我们建议在当地一所学校开展工作，我们在过去五年中与该学校建立了关系。我们将在12岁和16岁的两个大的队列（每个队列> 200）中测试音高、定时和音色域中不同水平的序列复杂性。这些受试者在听觉分析方面的技能与一系列标准化语言评估措施有关。我们将专门测试这两组中序列分析和语言技能之间的假设关系，并假设不同年龄段序列分析和语言之间的关系存在差异。我们还希望研究像音调记忆这样的序列分析的潜在基础。此外，我们建议研究序列分析和语言技能之间关系的可能大脑基础，这是建立在我们已经证明大脑顶叶的大脑结构与这两种技能之间存在相关性的基础上的。在纽卡斯尔大学的纽卡斯尔磁共振中心（NMR），我们可以使用磁共振成像对从年轻和老年人群中随机选择的人群进行非侵入性检查。这项工作的结果将是一个声音序列分析和语言技能及其大脑基础之间的关系的理解，作为未来的培训或干预策略的目标。

This work addresses the link between auditory skill and language proficiency. The ability to hear is essential to normal language acquisition: what is addressed here is whether particular skills in the analysis of auditory patterns are needed for language development. Many studies have examined the relevance of analysis of simple sound patterns in single sounds or pairs of sounds to language skill. We are interested in whether the analysis of more-complex sound sequences is of particular relevance to language skill. This has face value given that listeners are required to chop up the speech stream into the correct speech units before those units can be properly understood. We propose the hypothesis that sequence analysis based on a number of different cues is critical to speech understanding: sequences of pitch like melodies, sequences of time-intervals like rhythms and sequences of timbre or 'tone colour'. Sequence analysis requires high-level analysis in the auditory brain including the auditory cortex and continues to develop over adolescence. We propose to study the link between auditory analysis and language skill in early and late adolescence to examine the hypothesis based on our previous work (in early adolescence) that different types of sequence analysis are important at different stages of adolescence. To take rhythm as an example, in early adolescents there is a relationship between the analysis of simple regular rhythms (like that of a metronome) and language whilst in older subjects the relationship is with more abstract rhythms like when subjects are required to 'find a beat'. The work is important because many subjects fail to acquire language normally by listening to it. Evidence suggests that this process goes wrong in dyslexia, defined as a disorder of reading and spelling that is not explained by low intelligence or lack of opportunity. Dyslexia occurs in 5% of the population and causes lifelong problems to the individual and great costs to society. If we prove that there are critical links between auditory sequence analysis and language skill this would suggest new behavioural interventions based on auditory sequence training to help language. This would also suggest further investigation of the parts of the brain responsible for sequence analysis in order to understand developmental language disorder. We propose to carry out work at a local school with which we have developed a relationship over the last five years. We would test different levels of sequence complexity in the pitch, timing and timbre domains in two large cohorts (>200 each) at the ages of twelve and sixteen. The skill of these subjects in auditory analysis would be related to a battery of standardised language assessment measures. We would specifically test the hypothesised relationship between sequence analysis and language skill in these two groups and hypothesised differences in the relationship between sequence analysis and language at different ages. We also wish to examine underlying bases for sequence analysis like tone memory.Further, we propose to investigate possible brain bases for the relationship between sequence analysis and language skill that builds upon pilot work in which we have demonstrated that there is a correlation between brain structure in the parietal lobe of the brain and both skills. We can do this non-invasively using magnetic resonance imaging on random groups chosen from the younger and older cohorts at the Newcastle Magnetic Resonance Centre (NMR) of Newcastle University . The outcome of this work would be an understanding of the relationship between sound-sequence analysis and language skill and its brain basis, as a target for future training or intervention strategies.