Assessing the neural dynamics of reading in deaf adults

阅读能力差是一个重大的公共卫生问题，因为识字率低与许多负面的社会和经济后果有关(例如，就业机会不佳、获得保健信息的机会有限、公民参与度降低)。NIDCD 2017-2021年战略计划中的一个优先领域包括研究：“确定与使用手语作为主要交流方式的人成功理解和使用书面语有关的核心和外围因素(PG.48)“。为此，这个项目调查了支持成年手语者成功阅读的神经认知过程，这些人出生时就是聋人，或者在婴儿早期就变成了聋人。主要目标是使用心理语言学范式和事件相关电位(ERPs)来区分聋人在识别单个单词(目标1和2)、并行识别多个单词(目标3)和理解句子(目标4)时影响阅读回路功能的与耳聋相关的因素和与阅读相关的因素。目的1检验感觉依赖性神经可塑性对早期视觉和正字法加工的时间进程的影响，但对于阅读水平相当的聋人和听力读者来说，后期的词汇语义加工是相似的。目的2检验一种假设，即聋人读者在阅读形态复杂的单词时优先使用形态-语义路线，而拼写较好的人则利用形态-切分路线。目的3验证以下假设：由于与早期耳聋相关的空间注意分布的改变，聋人读者表现出更大的旁中央窝对中央凹的文字加工效应。目的4检验这一假设在句子级加工中的应用，并考察聋人读者对违反语法的事件相关电位反应(P600)的差异是否与违反的类型和/或早期语言剥夺有关。这些目标将通过创新的方法来实现，这些方法将ERPs与新颖的侧翼范例相结合，并与自然阅读过程中共同登记的眼球运动相结合。我们还使用线性混合效应回归来确定阅读、拼写和语音技能的连续测量对ERP成分的影响，使用的是单次试验脑电数据。该项目的结果将促进我们对阅读系统神经可塑性的理解，并将是为阅读能力较差的聋人制定有针对性的补救计划的关键。通过了解熟练的成年聋人读者如何弥补说话机会的减少，可以精心设计干预措施来促进这些技能。总体而言，该项目将帮助建立一个框架，以制定新的战略，以提高聋哑儿童和成年人的阅读技能。

Poor reading skills represent a significant public health concern because low literacy is associated with many negative social and economic outcomes (e.g., poor employment opportunities, limited access to health care information, reduced civic engagement). A Priority Area in NIDCD’s strategic plan for 2017-2021 includes research to “Identify central and peripheral factors associated with the successful comprehension and use of written language for people who use sign language as their primary way of communication (pg. 48)”. To that end, this project investigates the neuro-cognitive processes that support successful reading in adult signers who were born deaf or became deaf in early infancy. The primary goal is to use psycholinguistic paradigms and event-related potentials (ERPs) to differentiate deafness-related from reading-related factors that impact the functioning of the reading circuit when deaf adults recognize single-words (Aims 1 and 2), identify multiple words in parallel (Aim 3), and comprehend sentences (Aim 4). Aim 1 tests the hypothesis that sensory-dependent neural plasticity impacts the time course of early visual and orthographic processes, but that later lexico-semantic processes are similar for deaf and hearing readers with comparable reading levels. Aim 2 tests the hypothesis that deaf readers prioritize the morpho-semantic route for reading morphologically complex words but that better spellers utilize the morpho-segmentation route. Aim 3 tests the hypothesis that deaf readers exhibit greater parafoveal-on-foveal word processing effects due to changes in the distribution of spatial attention associated with early deafness. Aim 4 tests this hypothesis for sentence-level processing and also investigates whether the previously identified difference in the ERP response to grammatical violations (the P600) for deaf readers is due to the type of violation and/or to effects of early language deprivation. These aims will be achieved through innovative methods that combine ERPs with novel flanker paradigms and with co-registered eye-movements during natural reading. We also use linear mixed effects regression to identify the effects of continuous measures of reading, spelling, and phonological skills on ERP components using single trial EEG data. The results of this project will advance our understanding of the neuroplasticity of the reading system and will be key to creating targeted remediation programs for deaf adults with poor reading ability. By understanding how skilled adult deaf readers compensate for reduced access to speech, interventions can be crafted to promote those skills. Overall, this project will help build a framework for creating new strategies to improve reading skills in deaf children and adults.