Abstract:
Cognitive workload can affect the number of errors one makes during a task. Measuring
the cognitive load can be beneficial for understanding the factors effecting the performance
of an individual. There is a lot of research about the measurement of cognitive
workload, however a standard metric for cognitive workload estimation, applicable to
multiple situations does not exist.
In this study a task is designed to induce variable mental workload. This task varies
not only the intrinsic workload by changing the difficulty level of task, but also the
extraneous workload by varying the input methods (i.e. visual and auditory). Brain
waves of participants were recorded during the task using a commercially available single
channel EEG device having dry electrode at Fp1 location. Participants were also
asked to give the subjective feedback about the tasks using NASA-TLX questionnaire.
Power spectral densities of brainwaves are used for the estimation of mental workload
and results are verified using subjective feedback.
The results from experiments and power spectral densities of different brainwaves are
analyzed while comparing the relaxed and working state of participants. It helps us
conclude that single channel EEG device is able to differentiate between relaxed and
working state of brain. Similarly, while using the already available metrics of mental
workload, we observed that auditory task demands less mental resources as compared
to visual tasks. Still, those metrics are not sensitive enough to differentiate among the
different difficulty levels of a same task.
