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

发育性语言障碍(DLD)和自闭症是两种常见的神经发育疾病，语言习得受到干扰。自闭症会影响儿童与世界沟通和互动的方式。每100名儿童中就有一名患有自闭症，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状况。据估计，每个教室有两个孩子患有DLD。语言障碍对这些儿童的生活结果有严重影响，限制了他们的学业成就、就业前景以及社会和情感健康。一个可能促进学习--或加剧障碍--的因素是动机。患有这些疾病的儿童通常不喜欢或不追求阅读等基于语言的任务。这造成了一个恶性循环：那些不擅长语言的人脱离了语言，因此，他们努力提高语言水平。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促进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，我将重点放在动机和语言学习之间的联系，以及它们对DLD和自闭症的影响。最近方法上的进步，特别是在大脑成像和数学建模方面，现在让我们能够更深入地理解动机。我们可以问人们认为哪些东西本质上是有回报的，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提高学习效率。我计划第一次使用这些先进的方法来研究DLD和自闭症患者的语言学习动机。我将研究患有DLD和自闭症的儿童是否发现语言学习本质上是有回报的，以及内在动机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，评估授予的好处在DLD和自闭症方面是否有所不同。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学习语言比神经正常的人更不值得努力。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来支持这些孩子的语言学习。在其他人群中(例如多动症、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。这将帮助我们了解在DLD和自闭症中哪些区域或网络可能被破坏，并让我们更深入地了解群体之间的差异(例如，在DLD和自闭症中，不同的区域可能被破坏)。此外，患有DLD的儿童和有语言障碍的自闭症儿童都没有从神经科学的角度进行充分的研究，所以这项工作也将产生关于这些群体语言处理的重要信息。总而言之，奖励和动机在学习中扮演着关键角色，跨越各种任务和跨物种。然而，它们在语言学习中的作用还没有得到充分的研究。使用最先进的方法，我将研究语言处理与奖励和动机系统之间的相互作用，在DLD、自闭症和典型发展中。这将使我们深入了解语言学习的动机，揭示对神经型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疾病背后的生物学差异的了解。最终，我们可以开发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.