Mental workload and human performance in multitask

Mental workload often exceeds to pilots' cognition abilities with the increase of flight automatization. Accordingly, flight safety is threatened severely. It is necessary to provide pilots with appropriate mental workload during flying. A experiment of multitask which simulated the flight control environment with some degree of fidelity was developed. This work investigated how subjects perform four concurrent tasks (monitor, calculation-memory, attack and detect task) under different mental workload levels which achieved by changing working speed rhythm by measuring their reaction time and accuracy. Electroencephalograph was applied to measure subject's physiology reaction for searching the relation between mental workload and task difficulty. Result indicates that the subjects' performance is declining in series with the increase of mental workload. Subjects allot their attention,to lower mental workload. It is likelihood that there is non-sequence phenomenon of deterioration when concentrating on one characteristic task. Stimuli display time effects subjects' performance significantly though increasing stimuli display time can improve accuracy at the expense of increasing reaction time. The way frequency and high oscillation amplitude waves of electroencephalogram, to some extent, can reflect the scale of mental workload.