Objective <p>To explore the characteristics of cognitive potentials and their neuroregulatory mechanisms in patients with acute cerebellar ischemic stroke.</p> Methods <p>This study included 35 patients with acute cerebellar ischemic stroke and 70 healthy controls, admitted between June 2022 and July 2024. The Oddball paradigm was used to collect cognitive potentials from the P300 series, and the characteristics of the visual P3a and P3b components were analyzed. Dipole source reconstruction was performed for the P300 components in both groups, and the differences in source distribution between the two groups were analyzed.</p> Results <p>We found that in the patient group, the latencies of all components in the P300 wave were significantly prolonged, and the amplitudes of P2 and N2 in the P3a series were significantly reduced. Source analysis revealed changes or disruptions in the brain-cerebellum circuit connectivity in the patient group. Specifically, compared to the control group, the differences in P3b source distribution in the patient group were characterized by compensatory activation in the left cerebellar vermis, while the differences in P3a source distribution were characterized by disconnection between the cerebellum and the brain’s intrinsic network.</p> Conclusion <p>Following acute cerebellar ischemic stroke, delayed processing speed and reduced efficiency of visual information are observed, accompanied by impaired attentional control and behavioral decision-making in response to novel stimuli. Alterations or disruptions in cerebro-cerebellar circuit connectivity underscore the critical role of the cerebellar vermis in post-stroke cognitive processing.</p> Clinical trial number <p>Not applicable.</p>