Dual language learning as a training ground for sensory processing

声音是人类体验的重要组成部分，感知声音复杂性的能力会对生活质量产生重大影响，尤其是在嘈杂环境中听力变得更具挑战性的晚年。公众和科学界对寻找改善听觉处理的方法来克服这些挑战的兴趣越来越大。与音乐训练类似，会说两种语言被认为是有益于听觉处理的自然训练基地。然而，尽管双语在世界范围内普遍存在，但人们对双语对中枢听觉系统的结构和功能的影响知之甚少。这项研究对不断增长的说不止一种语言的美国人有影响。这项工作也有可能通过提供关于双语如何与老化的听觉系统相互作用的第一个数据来推进科学知识。通过教育和推广活动，研究结果将在现实世界的教育和临床环境中为实践提供信息。这个项目将测试一种假设，即双语会改变听觉中心的结构和功能，这是由于声音在两种语言的学习和交流中发挥了更大的作用。预测双语者的功能和结构可塑性有利于训练（语言）和未训练（非语言）刺激的听觉感知，并通过减少与年龄相关的功能衰退促进健康的听觉系统衰老。在大量的青年和中年人样本（n=200）中，该项目将使用磁共振成像（MRI）来测量听觉神经结构，使用频率跟随反应（ffr）来测量听觉功能，以及使用心理声学测试来测量语音和非语音刺激（例如噪音中的音调）的检测阈值。该数据集将重点关注从小就学习第二语言的双语者。在双语者中，结构和功能可塑性的程度被预测为反映双语经验的个体差异，包括双语熟练程度、使用程度和接触程度。因此，根据最近的趋势，双语能力不再被视为个体之间具有统一属性的单一变量，而是被视为一系列经验和能力。支持这一假设的初步研究是在使用有限刺激集的小群体中进行的；然而，一项综合的、大规模的研究尚未进行。本研究旨在填补这一空白。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Sound is an important part of the human experience and the ability to perceive sonic intricacies can have a large impact on the quality of life, especially later in life when hearing in noisy environments becomes more challenging. There is growing public and scientific interest in finding ways to improve auditory processing to overcome these challenges. Similar to musical training, speaking two languages has been proposed as a naturalistic training ground for benefiting auditory processing. Yet despite the worldwide prevalence of bilingualism, little is known about how the structure and function of the central auditory system are impacted by bilingualism. This research has implications for an ever-growing segment of the U.S. population who speak more than one language. This work also has the potential to advance scientific knowledge by providing the first data on how bilingualism interacts with the aging auditory system. Through education and outreach events, findings will inform practice in real-world educational and clinical contexts. This project will test the hypothesis that bilingualism alters the structure and function of auditory centers as a result of the increased role that sound plays in learning and communicating in two languages. Functional and structural plasticity in bilinguals is predicted to benefit auditory perception of both trained (language) and untrained (non-linguistic) stimuli and promote healthy auditory system aging by decreasing age-related functional declines. In a large sample of young and middle-aged adults (n=200), the project will use magnetic resonance imaging (MRI) to measure auditory neural structure, frequency-following responses (FFRs) to measure auditory function, and psychoacoustic tests to measure detection thresholds for speech and non-speech stimuli (e.g., tones in noise). The dataset will focus on bilinguals who learned their second language from an early age. Among bilinguals, the extent of the structural and functional plasticity is predicted to reflect individual variations in bilingual experience, including the degree of dual language proficiency, use, and exposure. Thus, following recent trends, bilingualism is not treated as a monolithic variable with uniform properties across individuals but instead, it is regarded as a spectrum of experiences and abilities. Preliminary studies supporting the hypothesis have been conducted on small populations using limited stimulus sets; however, an integrated, large-scale study has not been conducted. This research aims to fill this gap.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.