Gesa Hartwigsen, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig

Maintaining effective everyday communication across the adult lifespan requires adaptation to challenging conditions such as varying background noise, age-related cognitive decline, and brain lesions after stroke. How does the brain maintain fluent language processing when core systems are compromised? I propose that adaptation to communicative challenges is enabled by flexible recruitment of distributed brain networks, allowing functional plasticity across the adult lifespan. Using combined neurostimulation and neuroimaging, we investigate how the neural networks for speech and language processing in our brain reorganize in response to both transient and long-term perturbations. First, studies in healthy young adults demonstrate how neurostimulation can temporarily disrupt efficient language processing, revealing rapid, system-level network reconfiguration. Second, evidence from aging brains shows how plasticity supports compensation for gradual loss of function. Finally, data from individuals with stroke-induced brain lesions illustrate the brain’s capacity for long-term reorganization and recovery of language abilities. Together, these findings highlight how domain-general networks can support language processing under challenges, providing insight into flexible redistribution of function via systems-level plasticity.

Part 3 of 3 on a series of talks on the neurological underpinnings of language, organised by the TEAM research programme (Transdisciplinary Approaches to Learning, Acquisition, Multilingualism)