Reduced cerebral pressure-flow responses are associated with electrophysiological markers of attention in healthy older adults

Abstract

The aim of this study was to determine the effect of age on the relationship between cerebrovascular function and the neural bases of sustained attention. Twenty-seven healthy young adults (aged 18–30 years) and 24 older adults (60–75 years) underwent assessments of cerebrovascular function and sustained attention. Blood flow velocity of the middle cerebral artery was assessed via Transcranial Doppler Ultrasound, during seated rest, in response to hypocapnic breathing (cerebrovascular reactivity) and during a repeated sit-to-stand procedure (pressure-flow response). Attentional processing was assessed using the N2 and P3 components of the event-related potential during a two-tone auditory oddball task. Poorer pressure-flow responses were significantly associated with reductions in N2 and P3 amplitude in the old group (b = −0.50, p = .029 and b = −0.46, p = .045), but not the young group. These results suggest that alterations in the brain's capacity to combat reductions in perfusion pressure are associated with age-related differences in attentional processing, supporting the hypothesis that cerebrovascular hemodynamic disturbances play a role in age-related cognitive decline.