BackgroundMultiple sclerosis (MS) is a persistent inflammatory condition affecting the central nervous system, often associated with cognitive impairment. This impairment frequently presents itself as deficiencies in short-term memory, attention, and information processing speed. This research was designed to investigate P300 in patients with MS and its correlation with their cognitive function and their state of fatigue and depression. This work included two groups: the control group (20 subjects) and the study group (30 MS patients). Evaluation encompassed clinical history, audiological assessment, the Expanded Disability Status Scale (EDSS), the fatigue severity scale, the Beck Depression Inventory, Addenbrooke’s cognitive examination, and P300 component of event-related potentials (ERPs).ResultsThe study group exhibited varying degrees of fatigue and depression. The scores of Addenbrooke’s cognitive evaluation were reduced in the MS group. The MS group exhibited a considerably prolonged P300 latency compared to the control group.ConclusionThis study demonstrates the effectiveness of P300 in assessing cognitive function in persons diagnosed with MS.