Cognitive Workload Assessment: A Comprehensive Review

Abstract

Mental workload during high-effort tasks is a crucial measure of effective task performance. Maintaining cognitive demands within an individual's capacity enables the effective performance of complex multi-tasking. Conversely, surpassing this margin may lead to unpredictable and suboptimal performance. This review explores human mental workload assessment across real-world tasks like aircraft piloting, vehicle driving under challenging conditions, and automated power plant monitoring. Both subjective and objective monitoring methods are examined: subjective methods include the widely used NASA-TLX, while objective methods cover EEG and eye-tracking measures during task execution. Findings from these methods are correlated with overall task performance outcomes. Real-time workload monitoring provides distinct advantages in critical settings; for instance, if an operator’s cognitive capacity is reached, alerts could be triggered, or task demands adjusted to alleviate overload. Finally, a multi-modal analysis of the literature is presented, comparing the effectiveness of various monitoring technologies across different task domains to guide future research directions.