Functional and structural aging of the speech sensorimotor neural system: functional magnetic resonance imaging...

The ability to perceive and produce speech undergoes important changes in late adulthood. The goal of the present study was to characterize functional and structural age-related differences in the cortical network that support speech perception and production, using magnetic resonance imaging, as well as the relationship between functional and structural age-related changes occurring in this network. We asked young and older adults to observe videos of a speaker producing single words (perception), and to observe and repeat the words produced (production). Results show a widespread bilateral network of brain activation for Perception and Production that was not correlated with age. In addition, several regions did show age-related change (auditory cortex, planum temporale, superior temporal sulcus, premotor cortices, SMA-proper). Examination of the relationship between brain signal and regional and global gray matter volume and cortical thickness revealed a complex set of relationships between structure and function, with some regions showing a relationship between structure and function and some not. The present results provide novel findings about the neurobiology of aging and verbal communication.