An experimental new Android app developed by a team at Cornell University is designed to determine a person's alertness by examining their eyes. The app, called AlertnessScanner, utilizes a smartphone's front-facing camera to gauge the size of users' pupils. "When we're in an alert state, our sympathetic nervous system causes our pupils to dilate so that we can take in information more easily," reports New Atlas. "On the other hand, when we're tired, our parasympathetic nervous system causes our pupils to contract." From the report: In an initial study, test subjects were prompted to use the app to manually take photos of their pupils, once every three hours. Additionally, six times a day they completed a five-minute phone-based Psychomotor Vigilance Test (PVT), which is an established method of gauging reaction time. When the results of the two alertness-testing methods were compared, they were found to be very similar. That said, it was determined that most people wouldn't like having to make a point of using the app so many times every day. Additionally, in order to properly image the test subjects' pupils, the infrared filters of the phones' cameras had to be removed. The researchers managed to address these problems by changing it so that the app automatically takes a one-second-long burst of 30 pupil photos whenever users unlock their phones; and using a larger 13-megapixel front-facing camera.Read more of this story at Slashdot. Click here to read full news..