Visual Event-Related Potentials in Patients with Mild Cognitive Impairment

Abstract

Background: To compare the findings of visual event-related potential (ERP) in patients with mild cognitive impairment (MCI) and healthy individuals. Methods: Twenty patients (12 males, 8 females) diagnosed as MCI who received no treatment and 20 healthy individuals (14 males, 6 females) with no cognitive impairments were included to the study. To obtain visual ERP responses, 32 (rare) and 64 (frequent) angle checkerboard displays were used. Three channel recordings were performed from Fz, Cz, and Pz. Results: The mean age of the control and MCI groups were 66.0 ± 3.6 and 66.3 ± 4.4 years, respectively. No statistically significant difference was found in the mean age and distribution of gender between the groups. Visual ERP revealed that mean N200 and P300 latencies of the MCI group were significantly longer than controls. The longest N200 and P300 latencies were obtained from Fz. The mean P300 amplitudes were found to be significantly lower in patients with MCI. No significant difference was observed between the two groups with respect to N200 amplitudes. Conclusion: Visual ERP can be used to support MCI diagnosis. Although it is not a diagnostic test for cognitive impairment per se, it is an important, feasible, and noninvasive technique for evaluating the cognitive state.

Keywords

• dementia
• mild cognitive impairment
• visual event-related potentials