In a study announced in 2025, researchers described a thin electronic tattoo that sticks to the forehead to estimate mental workload. Its sensors read electrical activity from the brain and eye movements, while a small battery pack enables wireless use.

The sensors are customized to fit each person's facial features. In tests with six people doing memory tasks of increasing difficulty, brainwave patterns changed as mental demands rose.

The work comes from researchers at the University of Texas at Austin and collaborators.