Compared Evaluation Of B-Alert’s Encephalographic Workload Metrics Using An Operational Video Game Setup.
Résumé
When it comes to operational human factors studies, the use of a number of
different means (psychophysiological, questionnaires, performance indexes) to
complete expert behavioral observations allows specialists to issue practical
recommendations despite of the variability of the few operators involved. When it
comes to mental workload, literature has identified several different physiological
ways to assess it. We used Heart Rate Variability (HRV) and pupillometry for
previous works (ISAP’11, ’13) and both have strong limitations: HRV can only
be analyzed over 5-minutes time periods and pupil dilation is subject to light
variability.
During this study, we tested the electroencephalography B-Alert X10 system
(Advance Brain Monitoring, Inc.) mental workload metrics. We set up an
experiment on a video game in real life conditions in order to evaluate the
reliability of this index. Participants were asked to play a video game with
different levels of goal (easy vs. hard) as we measured subjective, behavioral and
physiological indexes (B-Alert mental workload index, pupillometry) of mental
workload. Our results indicate that, although most of the measure point toward the
same direction, the B-Alert metrics fails to give a clear indication of the mental
workload state of the participants. The use of the B-Alert workload index alone is
not accurate enough to assess an operator mental workload condition with
certainty. Further evaluations of this measure need to be done. As we observed in
a previous study, pupil dilation is a reliable index of mental workload as it
correlates significantly with most measures.