When Age Tips the Balance: a Dual Mechanism Affecting Hemispheric Specialization for Language

Abstract

Aging leads to neuroadaptations, often reducing specificity in functional brain responses. However, the extent to which functional specialization of brain hemispheres in the Language-and-Memory Network regions changes with adulthood remains unclear. In a cohort of healthy adults, we provide evidence that aging is linked to shifts in the cortical organizations lateralization, unveiling two age-related asymmetry patterns. The first pattern indicates a lateralization shift in language regions, with aging rendering language functions more bilateral. The second pattern reveals increased specialization in memory regions within the left hemisphere as we age. Manifesting around midlife, these shifts correlate with declines in language production performance. Our findings offer new insights into how functional brain asymmetries impact language proficiency and underscore brain plasticity in aging, providing a dynamic view of the aging brains functional architecture.