Scientists say device could alert workers such as pilots and healthcare staff when they are feeling the strainWhether it is doing sums or working out what to text your new date, some tasks produce a furrowed brow. Now scientists say they have come up with a device to monitor such effort: an electronic tattoo, stuck to the forehead.The researchers say the device could prove valuable among pilots, healthcare workers and other professions where managing mental workload is crucial to preventing catastrophes. Continue reading...