or nervous and under sympathetic stimulation under fight-or-flight your pupils dilate that allows you to see greater detail with more light bouncing off the things hitting your eyeball so that you can focus and see all the detail to escape or fight for your life you should know that now if you think for example if you're a police officer or emergency medical technician or working in the ER or the o.r and you think someone might be on speed or methamphetamine or cocaine or some kind of upper you can shine a bright light across the pupils if their pupils are massively dilated they're on a central nervous stimulant and if you shine a bright light and they don't constrict then you know something is overriding the brain's ability to do what it normally does there are some kind of CNS stimulants speed cocaine methamphetamine some kind of upper now if you shine a bright light on someone's eyes and they're constricted and you hold it there for a while and then you remove it and they don't dilate then there aren't some kind of CNS suppressant so it allows people to kind of figure it out sometimes if someone's nervous and lying if someone's tired or if they're on uppers or downers things like xanax and other things that kind of chill you out so some interesting information there now if you're following along on page 12 we've covered that information I'm going to stop here and I'm going to do the rest of the page on another set of lectures or in the next lecture because I've got to cut these in about thirty minutes or else you get some bearable to watch I'm trying to cover a lot of information but I don't want to go too fast because the goal here is to learn not just to cover information and if the videos get too long I can't load them into YouTube very easily so thanks for watching I hope this was helpful and you learned something we're gonna continue the eyeball in the next video I hope you have as much fun as I did see you in the next one