The development of lexical competition in heritage speakers

该奖项是作为NSF社会、行为和经济学博士后研究奖学金(SPRF)计划的一部分提供的。SPRF计划的目标是为学术界、工业界或私营部门和政府的科学职业生涯培养有前途的、早期职业博士水平的科学家。SPRF奖项包括在知名科学家的赞助下进行两年的培训，并鼓励博士后研究员进行独立研究。国家科学基金会致力于促进科学界所有阶层的科学家参与其研究方案和活动，包括那些来自代表性不足的群体的科学家；博士后阶段被认为是实现这一目标的专业发展的一个重要水平。每个博士后研究员都必须解决推动各自学科领域向前发展的重要科学问题。在爱荷华大学鲍勃·麦克默里博士的赞助下，这一博士后奖学金奖项支持一名早期职业科学家研究讲传统语言的儿童的语言发展。在当前的地理、政治和全球气候下，预计世界各地的移民人口将继续增加。这些移民的子女面临的一个关键障碍是语言，因为他们可能没有像只会说一种语言的儿童那样有机会发展他们新家园的大多数语言(VALDÉS，2005年)。因此，理解说传统语言的儿童的语言发展是一个挑战，因为他们的第一语言(传统语言)随着他们年龄的增长(通常在上学开始时)成为他们不那么主要的语言，而他们的第二语言(主要语言)最终成为主要语言，尽管起步较晚(Polinsky，2011)。这往往使他们沦落到特殊的英语学习者课堂，或者让他们得不到足够的支持。目前，传统语使用者在大多数语言中的支配地位是如何发展的，以及当这种语言支配地位转移发生时会发生什么样的神经变化，还没有得到很好的研究。这项研究旨在通过使用眼球跟踪、脑电和机器学习来了解口语识别，这是早期语言发展的一个瓶颈过程(Perfetti，2007；Verhoven，Reitsma，&Amp；Siegel，2011)，并在一年级和四年级的单语和传统说话者中进行。在这里，词汇处理--语言系统中的一个关键枢纽--被作为一个示范系统，在这个系统中询问说传统语言的人如何在大多数语言中变得更自动的语言处理器，并在他们的传统语言中保持这一点。评估说传统语儿童的语言背景是一项独特的挑战，因为他们接触的英语与他们的单语同龄人不同，他们的年龄和学习方式以及他们对大多数语言和传统语言的熟练程度不符合先前评估的双语标准。因此，典型的语言背景问卷可能不能充分反映说传统语言的儿童的经历。取而代之的是，采用了更全面的方法，包括创新的记录工具(即Lena系统)和网络科学，以量化两种语言的曝光率。最后，这项拟议的研究不仅旨在了解儿童时期延迟接触大多数语言的影响，而且了解其对讲传统语言的成年人语言表征的长期影响，并利用电生理和机器学习技术分离语义和听觉差异的贡献。这里的发现扩展了语言习得和不同双语人群(即说遗产的人)语言处理的认知神经科学。至关重要的是，遗产演讲者提供了洞察力，帮助回答词汇处理中理论上具有挑战性的问题，这些问题无法通过其他方式解决。总体而言，这项研究旨在扩大遗产演讲者在语言发展研究中的参与，并为遗产演讲者寻找和创建更可持续的语言和教育项目。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award was provided as part of NSF's Social, Behavioral and Economic Sciences Postdoctoral Research Fellowships (SPRF) program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Dr. Bob McMurray at the University of Iowa, this postdoctoral fellowship award supports an early career scientist examining language development in heritage speaker children. In the current geographical, political, and global climate, immigrant populations are expected to continue increasing around the world. A critical barrier faced by the children of these immigrants is language, as they may not have the same opportunities as monolingual children do to develop the majority language of their new home (Valdés, 2005). Thus, a challenge is posed for understanding the language development of heritage speaker children, as their first language (the heritage language) becomes their less dominant language as they age (often when schooling begins), and their second language (the majority language) eventually becomes dominant, despite a delayed start (Polinsky, 2011). This often relegates them to special English Language Learner classrooms or leaves them with insufficient support. Currently, how heritage speakers develop their dominancy in the majority language and what type of neural changes happen when this language dominancy shift occurs is not well-studied.The proposed research study aims to understand spoken word recognition, a bottleneck process of early language development (Perfetti, 2007; Verhoeven, Reitsma, & Siegel, 2011), in monolingual and heritage speakers at Grade 1, Grade 4, and in adulthood by using eye-tracking, EEGs, and machine learning. Here, lexical processing—a critical hub in the language system—is being targeted as a model system in which to ask how heritage speakers become more automatic language processors in the majority language and maintain this in their heritage language. Assessing heritage speaker children’s linguistic backgrounds presents a unique challenge in that their exposure to English is not similar to their monolingual peers, and their age and manner of acquisition as well as their proficiency in the majority and the heritage language do not follow previously assessed bilingual norms. Therefore, typical language background questionnaires may not adequately capture heritage speaker children’s experience. Instead, a more holistic approach, including an innovative recording tool (i.e., the LENA system) and network science to quantify the exposure in both languages are employed. Finally, the proposed study aims to not only understand the impact of delayed exposure to the majority language in childhood but also its prolonged impact on heritage speaker adults’ language representation, and to separate the contributions of semantic and auditory differences using electrophysiological and machine learning techniques. Findings here expand on both language acquisition and the cognitive neuroscience of language processing in various bilingual populations (i.e., heritage speakers). Crucially, heritage speakers provide insight to help answer theoretically challenging questions in lexical processing which cannot be otherwise addressed. Overall, this study aims to broaden the participation of heritage speakers in language development research as well as find and create more sustainable language and educational programs for heritage speakers.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.