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.<br/><br/>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.<br/><br/>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.