Study reveals new understanding of the brain regions used when learning to speak
Yale UniversityPeer-Reviewed Publication
Learning a new language — or learning to speak again after a stroke — involves a fine-tuned set of movements requiring precise coordination in brain networks. This includes the orofacial sensory system (input like touch and position from the lips, tongue, jaw, and face) and motor system (commands that move the muscles in the right way at the right time).
New study findings from researchers at Yale School of Medicine challenge a long-held assumption in neuroscience: that speech motor learning and the memory of newly learned speech movements are fundamentally driven by motor regions of the brain. Instead, the study findings indicate that retention of newly learned speech movements relies chiefly on sensory brain processes.
The work has implications for rehabilitation and emerging neurological technologies, pointing to the sensory cortex as a potential neural target for rehabilitation after a stroke or brain injury affecting speech. The findings may also inform brain-computer interfaces, by highlighting the relevance of sensory cortical activity for movement control. The results also suggest that speech-processing and -recognition technologies could improve by more explicitly integrating auditory and somatic sensory signals.
The study was led by Nishant Rao, an associate research scientist at Yale Child Study Center. “These findings establish a sensory basis for speech motor memory, indicating that plasticity in sensory brain areas is necessary for learning and retaining newly acquired speech movements,” Rao said.