A long-standing puzzle in psychology and the brain sciences is how the systems that underpin perception and cognition (e.g., vision, hearing, intention) are coordinated with those that generate action (e.g., reaching, speaking, walking). Although a great deal has been learned about how these individual systems work, how these critical functions interact remains poorly understood. This interaction is especially important in speech communication, which is of remarkable significance in humans. In order to use speech successfully, both to communicate with others and to monitor oneself speaking, the auditory speech perception circuit and the motor speech production system must precisely align in time. This temporal coordination is important for planning to speak, monitoring one’s errors, learning language sounds, and learning new words from a conversation. In this research program, the investigators study this alignment through auditory-motor synchronization. They use behavioral, neuroscience, and computational approaches to characterize auditory-motor synchronization and test the consequences of this synchronization for real-life behaviors such as word learning.
An important feature of recent work that motivates this research is the discovery of a simple behavioral paradigm, the “spontaneous speech synchronization test†(SSS test). The test measures how precisely listeners synchronize their own spoken output to speech that they hear. The procedure is remarkably sensitive to individual differences, revealing that not all listeners synchronize equally well. Notably, the synchronization scores from the SSS test not only correlate highly with brain anatomy and physiology but are also predictive of listeners’ performance in important real-life challenges, such as word-learning. The new research builds on the novelty, sensitivity, and broad utility of the SSS test. The research plan is organized into four aims. First, the investigators will optimize the test for broad use by other scientists. Second, they will perform new experiments that test how auditory-motor synchronization, i.e., the rhythmic alignment between speech perception and speech production systems, guides speech perception. Third, they will develop a computational model constructed to provide a mechanistic description as well as to generate further testable predictions of auditory-motor synchronization. Fourth, the team will explore the consequences of synchronization for the essential capacity of word learning. An overarching practical, final goal is to release the SSS test in an open access format. Because the test outcome correlates with word learning, specific patterns of neural connectivity, and other cognitive features, it can be a useful, quick, easy-to-implement assay for researchers, educators, and clinicians.
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.
