P300 event-related potential in patients with cognitive decline correlates with task performance

The conditions of subjective cognitive decline (SCD) and mild cognitive impairment (MCI) are two ordered stages in cognitive decline. The transition between the SCD stage and MCI is a phenomenon that largely depends on the individual's neurological characteristics. Monitoring these characteristics through non-invasive and portable methods such as electroencephalography (EEG) allows for extracting information that can be associated with the patient's clinical condition. Here, we investigated the differences between SCD and MCI in the P300 event-related potential obtained during a visual attention task. By looking central EEG channels (FC1, FCz, FC2, C1, Cz, C2), we compared the signals along the interval 300 [ms] - 500 [ms] between the two conditions, further stratifying for the task performance. We found that the P300 amplitude was larger in patient with a better performance, and that this effect was significantly more pronounced in MCI subjects. These results suggest that P300 during a simple task can be a useful neural marker to discriminate between the two conditions. In future longitudinal studies, this marker could support identify risk or protection profiles for conversion in the SCD and MCI continuum.