In comparison to Caucasian Americans, African Americans present increased risk of cerebrovascular events such as stroke (Roger et al. 2011), even after controlling for age, insulin‐dependent diabetes, hypercholesterolaemia and education (Sacco et al. 1995). The mechanisms explaining this increased prevalence of cerebral vascular disease in African Americans therefore remain elusive, though African Americans do demonstrate impaired endothelial function of systemic conductance arteries (Perregaux et al. 2000). If similar dysfunction exists in the cerebral circulation of African Americans, it could impair cerebral blood flow regulation and predispose to, or possibly trigger, cerebrovascular events.