Doctoral Dissertation Research: Neurobiological Correlates of Phonological Awareness and Reading Outcomes

阅读技能在年轻学习者和他们参与21世纪世纪经济的能力中发挥的核心作用突出了高识字率对创新劳动力的重要性。 阅读理解困难和随之而来的缺乏获得印刷思想和信息的机会，是一个问题，为广大人口的儿童与穷人的阅读技能（如贫困的城市和农村儿童，阅读障碍的儿童，和聋哑儿童）。 在这些人群中的研究发现，提高了我们对阅读发展的多样性的理解，并支持为各种类型的青少年读者制定最佳教学策略。聋人儿童的阅读能力各不相同，但平均而言，尽管听力技术取得了进步（例如，助听器和耳蜗植入物）以及数十年来提供对口语的可视访问的各种方法（例如，语音朗读，提示语音，签名精确英语）。通过研究成功的聋人读者，研究人员一再发现手语熟练度和阅读结果之间存在很强的相关性。不幸的是，目前还不清楚究竟是什么方面的手语熟练程度有助于阅读的结果在聋人儿童。听力儿童阅读能力的一个重要预测因素是语音意识（PA），即识别和操纵单词语音结构的能力，最近的行为研究发现，手语的PA与聋儿的阅读有关，但手语和口语的PA是否是共同认知机制的产物还不清楚。本项目将研究美国人PA的大脑基础。手语（ASL）和英语，并解决两个假设的语音意识和阅读发展的聋儿。口语语音依赖假说认为口语语音对阅读是必不可少的，聋儿的语音加工是延迟的而不是异常的。抽象的语音表征是从可接近的听觉信号和视觉发音线索（即，口腔运动），可以随着时间的推移而加强。语音表征是聋儿语音意识和阅读的基础，尽管存在延迟。根据情态独立假设，抽象语音表征与言语无关，而是非情态的。当儿童有早期，自然接触语言，无论模态，他们发展强大的语音表征，从而产生PA技能分割和操纵语音信息，可应用于学习阅读。 为了验证这些假设，我们将招募使用美国手语的聋哑儿童和在K - 6年级就读的听力单语英语者。所有儿童都将接受标准化的阅读理解和非语言智商评估。在进行功能性近红外光谱（fNIRS）神经成像的同时，我们将使用非正字法，非语言图片匹配范例评估ASL和英语PA的大脑基础。分析将调查PA在两种模式和阅读理解激活的大脑区域之间的关系。这项研究的结果有望推进我们对语言神经生物学的认识，并有助于聋儿识字教学的教育方法。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

The central role that reading skill plays in the young learner and their ability to engage in the 21st century economy highlights the importance of high literacy rates for an innovative workforce. Reading comprehension difficulties and concomitant lack of access to printed ideas and information is a problem for a wide range of populations of children with poor reading skills (e.g. poor urban and rural children, children with dyslexia, and deaf children.) Research discoveries in each of these populations have advanced our understanding of the diversity of reading development and supported the development of optimal instructional strategies for various types of young readers. Deaf children's reading abilities vary, but on average have remained far behind those of their hearing peers despite advancements in hearing technologies (e.g., hearing aids and cochlear implants) and decades of various approaches to providing visible access to spoken language (e.g., speechreading, Cued Speech, Signed Exact English). By examining successful deaf readers, researchers have repeatedly found examined strong correlations between sign language proficiency and reading outcomes. Unfortunately, it has remained unclear exactly what aspects of sign language proficiency contribute to reading outcomes in deaf children. One important predictor of reading abilities in hearing children is phonological awareness (PA), the ability to identify and manipulate the phonological structure of words, and recent behavioral research has found that PA for signed languages is related to deaf children's reading, but whether signed and spoken language PA are the product of a common cognitive mechanism remains unclear.This project will investigate the brain basis of PA for American Sign Language (ASL) and English and address two hypotheses of phonological awareness and reading development in deaf children. The spoken language phonology dependent hypothesis holds that spoken language phonology is essential for reading, and that phonological processing in deaf children is delayed rather than abnormal. Abstract phonological representations are assembled from the accessible auditory signal and visual articulatory cues (i.e., mouth movements) that can be strengthened over time. Though delayed, the phonological representations are the basis for phonological awareness and reading in deaf children. According to the modality independent hypothesis, abstract phonological representations are not tied to speech, but are amodal. When children have early, natural exposure to language, regardless of modality, they develop strong phonological representations which give rise to PA skills for segmenting and manipulating phonological information that can be applied to learning to read. To test these hypotheses, we will recruit deaf children who use ASL and hearing monolingual English speakers enrolled in grades K - 6. All children will be administered standardized reading comprehension and nonverbal IQ assessments. While undergoing functional near infrared spectroscopy (fNIRS) neuroimaging, we will assess the brain bases of ASL and English PA using a non-orthographic, non-linguistic picture-matching paradigm. Analyses will investigate the relationships between brain regions activated for PA in both modalities and reading comprehension. Findings from this study promise to advance our knowledge of the neurobiology of language and to contribute to educational approaches in literacy instruction with deaf children.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.