Functional magnetic resonance imaging with encoding task in patients with mild cognitive impairment and different severity of leukoaraiosis

•fMRI with encoding task differs in MCI cases according to different vascular damage.•Vascular MCI (vs controls) show areas of mainly left frontal hypoactivation.•Vascular MCI (vs controls) show areas of mainly right posterior hyperactivation.•Non vascular MCI (vs controls) show diffuse areas of hyperactivation.•Different fMRI patterns may reflect different patterns of damage and compensation. Leukoaraiosis is one of the main contributors to mild cognitive impairment due to vascular damage (vascular MCI, VMCI), whose pathophysiology has not been fully elucidated yet. We aimed to shed light on such issue using functional MRI (fMRI). Sixteen patients with VMCI were enrolled and compared with twenty-five patients with MCI but without significant vascular damage (non-vascular MCI, NVMCI) and with fifteen healthy controls (HC). They all underwent fMRI with incidental verbal learning paradigm, using a 3T scanner. Differently from cases with NVMCI (versus HC), VMCI patients presented a higher BOLD activation in the right parieto-occipital cortex and a lower activation in the left superior and middle frontal gyri, anterior cingulum and in left fronto-opercular area when compared to HC. Cortical activation evaluated by fMRI may reflect specific patterns of damage and attempt of compensation in patients with MCI and different severity of leukoaraiosis.