hashris martinez' father challenged others to act on gun control. everyone suffers from busy and slow days at work or what if your computer could tell if it was a stressful day? there is a brain sensor that can do just that. it could be used to our benefit. the computer normally does not know anything about you. -- it new nice if you that you are busy and struggling or coasting and adjusting in some way. sam has got this had been done. what exact the is going through these cables and what are we finding out? >> these are fiber-optic cables curing the light to the head and then back to this machine which measures how much light came back. we can find out how hard a particular part of the brain is working. >> you can tell how stressed someone is at work. getting bored.e >> what kind of practical use might this have? >> imagine a team of people who are flying a bunch of remotely piloted airplanes. they're playing can be handed off to someone else. what it does is shines light and measures light coming back. it is easy to imagine that this is a device f