Assessing Cognitive Capacityby P3During a Complex ManualControl Task

Abstract

Our aim was to adapt a classical P3 method to assess the free cognitive capacity during spacecraft docking training in space.Electroencephalogram (EEG) measurement in space is limited by several conditions. Based on experience with our own EEG experiments onMIR and ISS, we decided to use dry electrodes and restricted the electrode placement to the forehead. We examined whether P3 can bereliably obtained under these conditions. Subjects had to perform a manually controlled docking task simultaneously with an acousticmonitory task. The P3 component was evoked by the acoustic stimuli of the secondary task. Twenty-six subjects participated in this study,situated in a space simulation on earth. After a familiarization session, they performed the docking tasks at three difficulty levels: low,medium, and difficult. In the secondary task, subjects had to discriminate between a low (750 Hz) and a high (1,000 Hz) tone, which differed inprobability of 90% and 10%, respectively. The subjects had to count the high tone and after 10 relevant tones and had to give a voice commandto a power supply configuration. P3 amplitude was largest and the latency shortest during the medium difficult task. A decision matrix basedon differences between the relevant and irrelevant P3 was calculated for each subject and each task. The results suggest that P3 can berecorded during a complex manual control task and can be used to assess individual free cognitive capacity.