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熟练程度之间的联系。听力能力对正常的语言习得至关重要：这里讨论的是语言发展是否需要分析听觉模式的特殊技能。许多研究考察了对单音或成对发音中简单发音模式的分析与语言技能的相关性。我们感兴趣的是，对更复杂的声音序列的分析是否与语言技能特别相关。这是有表面价值的，因为听众需要将语音流砍成正确的语音单元，然后才能正确地理解这些单元。我们提出的假设是，基于许多不同线索的序列分析对语音理解是关键的：类似音调的旋律序列、类似节奏的时间间隔序列以及音色或音色序列。序列分析需要在包括听觉皮质在内的听觉大脑中进行高级分析，并在青春期继续发展。我们建议在青春期早期和晚期研究听觉分析和语言技能之间的联系，以检验基于我们之前的工作(在青春期早期)的假设，即不同类型的序列分析在青春期的不同阶段很重要。以节奏为例，在青少年早期，对简单规则节奏(如节拍器的节奏)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之间的关系，例如当受试者被要求找到节拍时。这项工作很重要，因为许多受试者无法正常地通过听来习得语言。有证据表明，这一过程在阅读障碍中出现了错误，阅读障碍的定义是阅读和拼写障碍，这是一种智力低下或缺乏机会无法解释的障碍。阅读障碍在5%的人口中发生，给个人带来终生问题，给社会带来巨大代价。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，这将建议基于听觉序列训练的新的行为干预措施来帮助语言。这也建议对负责序列分析的大脑部分进行进一步研究，以了解发育性语言障碍。我们计划在当地一所学校开展工作，我们在过去五年里与该学校建立了合作关系。我们将在12岁和16岁的两个大群体(每个群体200英镑)中测试不同水平的音高、时序和音色领域的序列复杂性。这些受试者在听觉分析方面的技能将与一系列标准化的语言评估措施有关。我们将在这两个群体中具体检验序列分析与语言技能之间的假设关系，并假设不同年龄段序列分析与语言技能之间的关系存在差异。我们还希望检查序列分析的潜在基础，如声调记忆。此外，我们建议调查序列分析与语言技能之间关系的可能大脑基础，这建立在试点工作的基础上，在这项工作中，我们已经证明了大脑顶叶的大脑结构与这两种技能之间存在相关性。我们可以通过对纽卡斯尔大学纽卡斯尔磁共振中心从年轻和年长队列中选择的随机组进行磁共振成像，以非侵入性的方式完成这项工作。这项工作的结果将是理解声音序列分析和语言技能及其大脑基础之间的关系，作为未来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.