Abstract: Objective To investigate the executive function in maintenance hemodialysis (MHD) patients. Method The event-related potential (ERP) of 16 MHD patients (MHD group) and 15 health people (healthy group) under Flanker task were analyzed. The accuracy and reaction time of key-press action were automatically
recorded. We performed analysis of variance (ANOVA) and simple effect test for the repeated measures to compare the differences in accuracy, reaction time, and the components of N200 and P300. Result There were no significant differences in accuracy (F [1,29]=0.881, P=0.176) and reaction time in consistency
situation between MHD group and healthy group. The reaction time under inconsistency situation was significantly longer in MHD group than in healthy group (P=0.028). The reaction time difference under Flanker interference was also significantly longer in MHD group than in healthy group (t=34.514,P<0.001). In both
MHD and healthy groups under consistent/inconsistent situations, the peak of N200 [F(1,28) =17.851, P< 0.001) and the amplititude of P300 [F(1, 29)=4.348, P=0.046] had the interaction between task type and group effect. Under consistent situation, the peak of N200 (P=0.912) and amplititude of P300 (P=0.049) had no significant differences between MHD group and healthy group. Under inconsistent situation, however, the peak of N200 (P=0.048) and the amplititude of P300 (P=0.049) were significant higher in MHD group than in healthy group. The group main effect of P300 latency was significant [F(2,56)=17.482, P<0.001]. Conclusion  The basic identification and basic reaction time were normal in MHD patients. However, their cognitive inhibition ability and conflict monitoring ability were impaired.

Key words: Flanker task, executive function, behavioral experiment,  Event-related potential