Transfer of statistical learning from perception to production

无论是在咖啡馆与朋友聊天，在课堂上讨论某个话题，还是与亲戚辩论政治，我们都依赖于与许多不同的人沟通的能力。 75 亿英语使用者中只有 5% 是母语人士，而且不同地区的英语也存在巨大的方言差异。因此，我们经常会遇到说话与我们不同的说话者。先前的研究表明，大脑协调听和说的联系可以使对话伙伴听起来更像彼此。听到的内容对说话方式的影响通常被称为“转移”。迁移提供了一个窗口，通过它可以更好地理解言语感知和言语产生之间的机制联系。这很重要，因为它为跨多个领域产生更广泛的影响奠定了基础，例如：1）开发新技术，在具有语言多样性的课堂上实现有效的教育方法； 2) 帮助个人解决口吃等沟通难题； 3）为完善人工智能和机器语音识别系统提供约束； 4）设计大脑假体，可以恢复因中风而丧失的语言能力。当前的项目重点是了解大脑如何将我们听到的内容与我们说话的方式联系起来，即使变化是微妙的并且无法有意识地识别。研究人员采用一种新颖的方法来研究迁移，以微妙但系统的方式操纵语音流的构成。如果生产受到感知的隐式影响，则该方法可以清晰地预测生产的预期变化。初步数据表明情况确实如此：通过操纵音调来创造微妙的口音，会导致扬声器产生相同维度的方式发生剧烈变化。这种影响不仅仅是立即模仿听到的言语（例如，重复刚刚听到的单词）。相反，它意味着对说话者的生产系统进行更根本的改变，这可能涉及通过对大脑进行微小但持久的神经可塑性变化来进行某种形式的增量学习。当前的项目将系统地调查转移何时以及如何发生，以揭示责任机制。该奖项反映了 NSF 的法定使命，并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，被认为值得支持。

Whether chatting with a friend at a café, discussing a topic in a classroom, or debating politics with a relative, we depend on our ability to communicate with many different people. Only 5 percent of the 7.5 billion English speakers are native talkers and there are also tremendous dialect differences in regional English. Thus, we quite often encounter a speaker whose speech differs from our own. Prior research demonstrates that links in how the brain coordinates listening and speaking can lead conversation partners to sound more like one another. The influence of what one hears on how one talks is often referred to as “transfer.” Transfer provides a window through which to better understand the mechanistic links between speech perception and speech production. This is important because it provides a foundation for broader impacts across a variety of domains, such as: 1) developing new technologies for effective education approaches in classrooms with language diversity; 2) assisting individuals with communication challenges like stuttering; 3) providing constraints to refine artificial intelligence and machine speech recognition systems; and 4) engineering brain prostheses that can restore speech lost to stroke.The current project focuses on understanding how the brain links what we hear with how we speak, even when changes are subtle and not consciously identifiable. The investigators take a novel approach to the study of transfer by manipulating the make-up of the speech stream in subtle but systematic ways. This method allows clear predictions about the expected changes to production if it is implicitly influenced by perception. Preliminary data suggest this is the case: creating a subtle accent by manipulating the pitch of a voice induces robust changes in how speakers produce the very same dimension. This influence goes beyond immediate imitation of heard speech (for example, repeating a just-heard word). Rather, it implies a more fundamental change to the speaker’s production system that likely involves a form of incremental learning through small, but persistent, neuroplastic changes to the brain. The current project will systematically investigate when and how transfer occurs in order to reveal the responsible mechanisms.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.