Researchers from the Institute for Aerospace Technology (IAT) at the University of Nottingham in the UK have collaborated with the Bioengineering and Human Factors Research Groups to use a non-invasive thermal camera for demonstrating the correlation between facial temperatures and mental workload.
The monitoring study revealed that the effect is most noticeable above the sinuses around the nose. Facial temperatures also decreased as the difficulty of the task increased among the participants.
It was observed that complete focus on a task changed the breathing rate due to the dominance of the autonomic nervous system, while the blood flow from the face might be potentially diverted to the cerebral cortex with an increase in mental demand.
Non-invasive and non-obtrusive monitoring of cognitive workload is considered important in areas where extreme cognitive demands could result in oversights and use errors.
Advances in digital thermography are said to have enabled the use of light and small cameras in an aircraft’s cockpit for the study.
Further enhancements to resolution and computing power are expected to facilitate the use of expert systems that can be programmed to recognise operators and their reaction to different mental demands.
The first author of the study and early-stage researcher Adrian Marinescu said: “The preliminary results are promising.
“Of all the approaches we’ve tried, facial thermography is the least intrusive, and has proved to be an excellent method – it’s convenient, gives real-time data, and the cameras have been getting smaller, lighter, and more affordable.”