The Effect of Mental Fatigue on Response Processes: An ERP Study in Go/NoGo Task

The effects of mental fatigue on response processes were examined using event-related brain potentials in this study. Twenty subjects were requested to perform a 2-back task for 100 min continuously which was used as the inducement of mental fatigue, meanwhile they were required to perform a 10-min Go/NoGo task (pretest) before and after the 2-back task (posttest) respectively. The subjective scores of fatigue scales, behavioral performance and electroencephalogram were recorded during the whole experiment. Increased fatigue scale scores and impaired performance demonstrated mental fatigue was indeed induced. In ERP analysis, paired T-test was used to analyze Go/NoGo-P3, Go/NoGO-N2 and ERN/Pe between the pretest and posttest and the results were as follows: The amplitude of NOGO-P3 decreased significantly (P < 0.05), while latencies of NOGO-P3/N2 and GO-P3 increased (all P < 0.05). Larger ERN amplitude was evoked by erroneous response to NoGo trials (P < 0.05). These results suggested that mental fatigue attenuated the response processes, and the metrics above are possible indices for measuring mental fatigue.