Measuring the blink of an eye
Eyelid movements can reveal a lot about the state of the brain.
The speed of a person's blink reflex can reveal neurological damage and conditions such as Parkinson's disease. It's tricky to measure, though: until recently patients had to wear cumbersome and uncomfortable electrodes, which meant that the test was rarely used.
A new device using a high-speed camera a fast digital processing may change all that.
The device - called a non-invasive blink reflexometer - is described in a paper in the IEEE Journal of Translational Engineering in Health and Medicine.