Evaluation of Mental Workload Associated With Time Pressure in Rapid Serial Visual Presentation Tasks

Abstract

Existing studies related to brain-computer interface (BCI) based on rapid serial visual presentation (RSVP) mainly focused on performance improvement or paradigm expanding. However, less work was reported about evaluating mental workload in RSVP tasks applied in surveillance field. This paper aimed to validate the separability of multi-levels of mental workload associated with time pressure in RSVP tasks, and additionally to explore the influence of mental workload on target detection performance and neural patterns. Time pressure was simulated by setting three levels of presentation rate. Both behavioral and single-trial target detection performance presented a descending trend as an increase of presentation rate. The changes of mental workload mainly affected occipital N2 and P3 components, whose amplitudes presented significantly negative correlation with z scored Rating Scale Mental Effort (RSME) value and significantly positive correlation with z scored single-trial hit rate. The average classification accuracy on three levels of mental workload reached to 71.0%. This work implies that the parameter associated with time pressure could affect the mental workload in RSVP tasks, and further influence the neurophysiological system and task performance. Mental workload induced by different presentation rates could be effectively estimated, which provides a potential approach to monitor mental workload in RSVP-BCI.