Verbal and Spatial Working Memory Impairment in Mild Cognitive Impairment Patients with Liver-Qi Depression Syndrome: An Event-Related Potential Study

This study delves into the investigation of verbal and spatial working memory impairments in mild cognitive impairment (MCI) patients, focusing particularly on those with liver-qi depression syndrome (LQDS). Event-related potential (ERP) techniques were employed for this investigation. Twenty-six healthy young subjects were recruited for an ERP experiment to validate the Chinese version of the Letter-Number n-back experimental paradigm. The study also involved the selection of MCI patients with LQDS (MCI group) and normal middle-aged and older adults (NC group) through questionnaire surveys, with 14 participants in each group. The ERP technique explored the P2 and P300 components related to verbal and spatial working memory in the three groups (MCI patients with LQDS, NC group, and youth group) under various tasks. Results showed that as the task load increased, all three groups displayed a significant decrease in accuracy and reaction time. The MCI group demonstrated the lowest accuracy and reaction time, while the youth group exhibited the highest values. Additionally, P300 latency was observed to be shorter in the MCI group compared to the NC and youth groups, suggesting a potential sensitivity index for detecting early decline in MCI patients with LQDS. In conclusion, this study highlights the overall cognitive function decline in MCI patients with LQDS, with the most prominent changes observed in behavioral responses. The results suggest that P300 could serve as a potential marker for detecting the early stages of decline in this population.