A chilly office isn't necessarily the reason why your nose feels icy while you work. As The Telegraph reports, a study in the journal Human Factors suggests that when your brain is overloaded, blood flow gets diverted from your facial extremities to your neurons, resulting in a cold nose.

To examine how our bodies respond to heavy mental workloads, University of Nottingham researchers monitored 14 volunteers with thermal imaging cameras as they completed a computer game with varying stages of difficulty. The subjects periodically ranked how hard they were working using scales and questionnaires. The researchers also measured the group's heartbeats, breathing rates, and pupil dilation. (Four participants dropped out during the course of the study, and most of the subjects were men. The authors noted that their main limitation was the sample size.)

Results ranged among subjects, but researchers found that nose temp dropped about 1.8°F among subjects who indicated they felt overwhelmed. That, plus pupil diameter, were good overall predictors of intense cognitive performance. Scientists say this is because blood is being diverted to the brain, and it takes extra energy to pump blood to the nose.

As the study points out, both excessively high and low levels of mental demand can hurt job performance. They hope to use these techniques to monitor workers like airline pilots, whose intense workload can lead to unsafe flying conditions if not managed properly.

[h/t The Telegraph]