Linking event-related potentials and structural MRI in the aging brain

Abstract

Aging alters both brain structure and electrophysiology, which can be measured non-invasively by structural magnetic resonance imaging (MRI) and event-related potentials (ERPs). On average, gray matter declines steadily from early adulthood, whereas white matter increases into midlife before declining. With respect to ERPs, the well-established P300 response shows reduced amplitude and delayed latency from early adulthood onward. Few studies test whether structural MRI and ERP measures correlate within the same individuals, and those that do disagree over which tissue tracks which ERP change. While ERP changes are not coupled to structural changes in a fixed manner, atrophy in gray and white matter tissue correlate with ERP response decay, and a clear pattern of structure–function coupling emerges with age. This dynamic in turn is magnified by age and disease. Technological advances are now enabling structural MRI and portable ERP to be collected from the same individual in a single visit, with machine learning able to model the two modalities jointly rather than separately. While clinical cohorts have historically been the starting point, healthy normative data sampled across the adult age range represents the foundational baseline. Establishing this coupling directly is the critical first step toward integrating MRI and ERP as mutually informative rather than parallel measures of the aging brain. Accordingly, this brief review assembles the evidence as a conceptual framework for linking MRI and ERP changes in healthy aging to support preclinical detection of cognitive decline, now enabled through recent technological advances.