Reward and motivation mechanisms supporting language learning: a cross-syndrome investigation of Developmental Language Disorder (DLD) and autism

发展性语言障碍（DLD）和自闭症是两种常见的语言习得中断的神经发育疾病。自闭症影响儿童与世界交流和互动的方式。每100个儿童中就有一个患有自闭症，70%的自闭症儿童面临终身语言障碍。DLD是一种以理解和使用语言持续困难为特征的神经发育疾病。每个教室估计有两名儿童患有DLD。语言障碍对这些孩子的生活结果有严重的影响，限制了他们的学业成就、就业前景、社会和情感健康。有一个因素可以促进学习，或者加剧障碍，那就是动机。患有这些疾病的儿童通常不喜欢或从事以语言为基础的任务，如阅读。这就形成了一个恶性循环：那些不擅长语言的人脱离了语言，因此，他们很难在语言方面做得更好。然而，目前关于这两种情况的认知模型在很大程度上忽视了动机的作用。了解如何通过提高动机来提高语言学习，可以帮助我们从现有的或新的干预措施中获得更好的结果。在这个项目中，我专注于动机和语言学习之间的联系，以及它们在DLD和自闭症中的破坏。方法的最新进展，特别是在脑成像和数学建模方面，现在使我们能够更深入地理解动机。我们可以询问人们认为哪些东西本质上是值得的，并量化他们会付出多少努力来获得这些东西。至关重要的是，这些研究揭示了动机可以促进学习。我计划首次使用这些先进的方法来研究DLD和自闭症的语言学习动机。我将研究患有DLD和自闭症的儿童是否会发现语言学习在本质上是有益的，以及内在动机的状态是否可以用来改善学习。我还将研究外部社会和非社会奖励在语言学习中的作用，评估在DLD和自闭症中所赋予的好处是否不同。最后，我将开发一个新的任务来量化努力，并评估患有DLD或自闭症的人是否认为语言学习不如神经正常的人值得努力。这项工作将帮助我们了解我们可能需要对学习环境做出哪些改变，以支持这些孩子的语言学习。在其他人群中（如多动症、帕金森氏症），动机的差异与大脑中的特定回路有关。我们建议使用类似的成像技术来检查涉及语言处理和动机的神经区域的大脑结构和功能。这将帮助我们了解哪些区域或网络可能在DLD和自闭症中被破坏，并让我们更深入地了解群体之间的差异（例如，不同的区域可能在DLD和自闭症中被破坏）。此外，从神经科学的角度来看，DLD儿童和有语言障碍的自闭症儿童都没有得到充分的研究，因此这项工作也将提供有关这些群体语言处理的重要信息。总之，奖励和动机在各种任务和物种的学习中起着至关重要的作用。然而，它们在语言学习中的作用尚未得到充分研究。使用最先进的方法，我将研究语言处理与DLD，自闭症和典型发展中奖励和动机系统之间的相互作用。这将使我们深入了解语言学习的动机，揭示对神经正常儿童有效的方法是否适用于DLD和自闭症。此外，通过了解这些群体中特定的大脑中断，我们将能够推进我们对这两种情况背后的生物学差异的了解。最终，我们可以制定更有针对性的干预措施来促进语言学习，改善这些群体的生活结果。

Developmental language disorder (DLD) and autism are two common neurodevelopmental conditions in which language acquisition is disrupted. Autism affects how children communicate and interact with the world. One in every 100 children has autism, and 70% of autistic children face lifelong language difficulties. DLD is a neurodevelopmental condition characterised by persistent difficulties with understanding and using language. Two children in every classroom are estimated to have DLD. Language difficulties have a severe impact on these children's life outcomes, limiting academic achievement, job prospects, and social and emotional well-being. One factor that could facilitate learning - or exacerbate impairments - is motivation. Children with these conditions often do not enjoy, or pursue, language-based tasks such as reading. This creates a vicious cycle: those who are not good at language disengage from language, and consequently, they struggle to get better at language. Yet, current cognitive models of these two conditions largely neglect the role of motivation. Understanding how to enhance language learning by improving motivation could help us achieve better outcomes from existing or novel interventions. In this project, I focus on the links between motivation and language learning, and their disruption in DLD and autism.Recent advances in methods, particularly in brain imaging and mathematical modelling, now allow us to understand motivation in far greater depth. We can ask which things people find intrinsically rewarding, and quantify how much effort they will exert to obtain them. Crucially, these studies reveal motivation can enhance learning. I plan to use these advanced approaches to study motivation for language learning in DLD and autism for the first time. I will examine if children with DLD and autism find language learning intrinsically rewarding, and if states of intrinsic motivation can be used to improve learning. I will also examine the role of external social and non-social rewards for language learning, assessing if conferred benefit differs in DLD and autism. Finally, I will develop a new task to quantify effort, and assess whether people with DLD or autism perceive language learning as less worthy of effort than neurotypical people. This work will help us understand what changes we might need to make to the learning environment to support language learning for these children.In other populations (e.g. ADHD, Parkinson's disease), differences in motivation have been linked to specific circuits in the brain. We propose to use similar imaging techniques to examine brain structure and function in the neural regions involved in language processing and motivation. This will help us understand which regions or networks might be disrupted in DLD and autism, and give us greater insight into the differences between groups (for instance, different regions may be disrupted in DLD and autism). Additionally, both children with DLD and those with autism who have language difficulties are understudied from a neuroscientific standpoint, so this work will also yield important information about language processing in these groups.In summary, reward and motivation play a crucial role in learning, across a variety of tasks and across species. Yet, their role in language learning is under-studied. Using state-of-the-art methods, I will study the interaction between language processing and reward and motivation systems in DLD, autism, and typical development. This will give us insight into motivation for language learning, shedding light on whether methods that are effective for neurotypical children hold in DLD and autism. Further, by understanding specific brain disruptions in these groups, we will be able to advance our knowledge of the biological differences underlying these two conditions. Ultimately, we can develop more targeted intervention to boost language learning, improving life outcomes in these groups.