Understanding Mental Workload

Imagine two pilots completing the same landing.

Or two students solving the same mathematics problem.

Both arrive at the correct outcome, yet one experiences the task as routine while the other works at the limits of their cognitive capacity.

Performance alone cannot explain that difference.

Researchers describe the cognitive effort required to perform a task as mental workload. Understanding how mental workload changes throughout an activity helps investigators study attention, decision-making, and human performance across a wide range of real-world environments.

Traditional assessments remain essential for measuring outcomes such as accuracy, completion time, and error rates. These metrics reveal what participants accomplished, but they do not always explain how demanding a task was while it was being performed.

Researchers increasingly want to answer a different question:

How much cognitive effort did the task require?

To better understand that experience, many studies combine behavioral assessments with physiological measurements, including electroencephalography (EEG), creating a more complete picture of cognitive demand throughout an activity [1]-[5].

Measuring Cognition as It Happens

EEG records the brain's electrical activity throughout a task, providing continuous physiological data that complements traditional behavioral assessments.

Rather than replacing existing research methods, EEG offers another perspective on how mental workload changes as participants learn, solve problems, operate vehicles, or interact with complex systems.

Together, these approaches help researchers investigate cognition as it unfolds rather than relying solely on task outcomes.

What Is Mental Workload?

Mental workload refers to the cognitive effort required to perform a task.

Unlike physical workload, which describes bodily exertion, mental workload reflects the demands placed on attention, working memory, information processing, and decision-making.

Mental workload is not determined by how difficult a task appears. Instead, it reflects how demanding that task is on the brain.

Understanding these demands helps researchers investigate how people interact with technology, learning environments, vehicles, healthcare systems, and other cognitively complex environments.

Mental Workload vs. Cognitive Load

Mental workload and cognitive load are closely related, but they describe different aspects of cognition.

Cognitive load most often refers to the mental demands associated with learning and working memory. It is widely studied in education research and instructional design.

Mental workload is broader. Researchers investigate it across transportation, aviation, healthcare, manufacturing, human-computer interaction, education, and other environments where people perform cognitively demanding tasks.

As researchers sought to better understand cognition during authentic activities rather than only controlled laboratory experiments, the interdisciplinary field of neuroergonomics emerged to study how the brain supports human performance in real-world environments [1], [2].

Why Researchers Measure Mental Workload

Understanding mental workload helps researchers answer questions that performance metrics alone cannot.

For example:

• How cognitively demanding is a task?

• When does workload begin to increase?

• How do people adapt as task complexity changes?

• Which interfaces reduce unnecessary cognitive effort?

• How does workload influence attention, decision-making, and overall performance?

These questions help researchers evaluate not only whether participants completed a task successfully, but how they experienced that task while performing it.

How Researchers Measure Mental Workload

Researchers rarely rely on a single measurement.

Instead, studies often combine several complementary methods, including:

• Behavioral performance

• Accuracy and error rates

• Task completion time

• Subjective workload assessments, such as NASA-TLX

• Eye tracking

• Physiological measurements, including EEG

Each method contributes different insights. Together, they provide a more comprehensive understanding of cognitive demand than any single measurement alone [1]-[5].

What Research Tells Us

Mental workload changes throughout a task.

Studies using wireless EEG during working memory experiments, including the n-back task, demonstrate that cognitive demand fluctuates continuously rather than remaining constant throughout an activity [4]. These measurements provide additional context that complements traditional behavioral assessments.

Mental workload can be studied outside the laboratory.

Recent research has used portable EEG systems to investigate mental workload during real-world driving. Rather than relying on simulated environments, researchers collected brain activity while participants navigated local streets, arterial roads, and highways, demonstrating both the feasibility of wireless EEG and the influence of changing road conditions on cognitive demand [1].

Mental workload research continues to expand.

Researchers are increasingly applying EEG to aviation, where studies investigate workload across different phases of flight [2], [5], as well as human-machine interaction, including unmanned aerial vehicle (UAV) traffic control [3].

Together, these studies illustrate an important shift in cognitive science. Rather than limiting investigations to controlled laboratory experiments, researchers are increasingly studying cognition where people naturally learn, work, travel, and make decisions.

From Laboratory Studies to Real-World Research

Studying cognition in authentic environments presents challenges that cannot always be recreated in a laboratory.

Drivers respond to changing traffic conditions.

Pilots adapt to dynamic flight environments.

Students learn in classrooms.

Operators manage increasingly complex technologies.

Wireless EEG makes it possible to investigate mental workload while participants engage in these natural activities, helping researchers better understand cognition where it occurs [1]-[5].

This evolution reflects a broader movement toward studying human performance in the environments it was designed to navigate.

Selecting an EEG System for Mental Workload Research

Different research questions require different EEG systems. Selecting the appropriate system depends on the study design, recording environment, participant population, and research objectives.

Flex Gel and Flex Saline

Flex supports configurable electrode placement with up to 32 EEG channels, making it well suited for advanced neuroergonomics, human factors, and cognitive neuroscience research. Its wireless design allows participants to move naturally while researchers collect high-quality EEG data in laboratory and real-world environments.

Epoc X

Epoc X is a 14-channel wireless EEG headset designed for cognitive neuroscience, neuroergonomics, and mobile research. It provides research-grade EEG acquisition in a streamlined system suitable for both controlled studies and field research.

Insight

Insight is a lightweight five-channel wireless EEG headset designed for rapid deployment in education research, usability studies, and other investigations where portability and ease of use are priorities.

The Future of Mental Workload Research

As technology becomes increasingly integrated into everyday life, understanding mental workload will continue to grow in importance.

Researchers are expanding beyond controlled laboratory experiments to investigate cognition in classrooms, vehicles, healthcare environments, and other real-world settings.

By combining behavioral assessments with continuous physiological measurements, EEG provides another lens through which researchers can investigate how people think, adapt, and perform during complex tasks.

Key Takeaways

• Mental workload describes the cognitive effort required to perform a task.

• Mental workload and cognitive load are related but serve different research purposes.

• Researchers combine behavioral assessments, subjective measures, and EEG to investigate cognitive demand.

• Wireless EEG is expanding mental workload research into authentic real-world environments.

• Selecting an EEG system begins with the research question and study design.

Put Your Framework Into Practice

You've explored how researchers investigate mental workload by combining behavioral assessments with continuous physiological measurements. Compare Emotiv EEG systems to identify the channel configurations, mobility, and research capabilities that best support your mental workload research objectives.

Compare EEG Systems

Suggested Reading

• What Cognitive Load Research Can Teach Us About Learning

• Measuring Attention with EEG: Looking Beyond Behavioral Assessments

• How EEG Is Helping Researchers Design Better Learning Environments

• Academic Research & Education Solutions

• Performance Metrics Explained

References

[1] H. Atici-Ulusu, O. Taskapilioglu, and T. Gunduz, "A Neuroergonomics Approach to Investigate the Mental Workload of Drivers in Real Driving Settings," Transportation Research Part F: Traffic Psychology and Behaviour, vol. 103, pp. 177-189, 2024.

[2] A. Hernández-Sabaté, J. Yauri, P. Folch, D. Álvarez, and D. Gil, "EEG Dataset Collection for Mental Workload Predictions in Flight-Deck Environment," Sensors, vol. 24, no. 4, 2024.

[3] F. Bazzano et al., "Mental Workload Assessment for UAV Traffic Control Using Consumer-Grade BCI Equipment," Lecture Notes in Computer Science, 2017.

[4] "Using Wireless EEG Signals to Assess Memory Workload in the n-Back Task," IEEE, 2016.

[5] "Identification of Pilots' Mental Workload Under Different Flight Phases Based on a Portable EEG Device," IEEE, 2023.