1 00:00:00,000 --> 00:00:07,920 I checked the internet and found that much of NASA's sleep research is being conducted 2 00:00:07,920 --> 00:00:12,160 in cooperation with Harvard Medical School through the National Space Biomedical Research 3 00:00:12,160 --> 00:00:14,600 Institute. 4 00:00:14,600 --> 00:00:18,640 Right now I'm looking for Brigham and Women's Hospital. 5 00:00:18,640 --> 00:00:23,680 That's where Dr. Charles Zeisler works conducting sleep research for NASA, inside specially 6 00:00:23,680 --> 00:00:24,680 designed rooms. 7 00:00:24,680 --> 00:00:28,640 By varying the lighting over time, he's helping astronauts understand the sleep challenges 8 00:00:28,640 --> 00:00:32,960 they may face when they travel to the moon, Mars, or planets beyond. 9 00:00:32,960 --> 00:00:36,720 Dr. Zeisler, what is a circadian clock? 10 00:00:36,720 --> 00:00:40,520 All living organisms have a circadian or biological clock. 11 00:00:40,520 --> 00:00:43,200 In mammals, it's located within the brain. 12 00:00:43,200 --> 00:00:47,680 This clock helps to synchronize body functions with the external environment. 13 00:00:47,680 --> 00:00:52,200 Through its connections with the eye, the brain receives information about the external 14 00:00:52,200 --> 00:00:54,120 light-dark cycle. 15 00:00:54,120 --> 00:01:01,400 By coordinating the body's biological clock with sunrise and sunset, the clock resets, 16 00:01:01,400 --> 00:01:06,000 helping to synchronize the rhythms that optimize the body for daily living. 17 00:01:06,000 --> 00:01:10,520 Without light-dark cues, most individuals would go to bed and wake up later each day. 18 00:01:10,520 --> 00:01:11,520 Why is that? 19 00:01:11,520 --> 00:01:16,200 R.J., it's because most people's biological clocks are set to cycle with a slightly longer 20 00:01:16,200 --> 00:01:18,680 than 24-hour period. 21 00:01:18,680 --> 00:01:22,240 Astronauts typically lose two hours of sleep every night. 22 00:01:22,240 --> 00:01:26,880 Once they are seven to ten days into a mission, their performance can be impaired as if they 23 00:01:26,880 --> 00:01:29,040 had stayed up all night. 24 00:01:29,040 --> 00:01:31,640 Can't you just catch up on your sleep later? 25 00:01:31,640 --> 00:01:32,640 Not really. 26 00:01:32,640 --> 00:01:36,780 In some situations, sleep loss can't be avoided, R.J., but it's something that everybody should 27 00:01:36,780 --> 00:01:38,120 try to limit. 28 00:01:38,120 --> 00:01:42,640 Our research shows that the body needs a consistent amount of sleep each night, particularly during 29 00:01:42,640 --> 00:01:44,520 growth and development. 30 00:01:44,520 --> 00:01:46,240 Take your case, R.J. 31 00:01:46,240 --> 00:01:50,480 Studies show that you need nine to ten hours of sleep each night to perform your best in 32 00:01:50,480 --> 00:01:52,960 school and on the field. 33 00:01:52,960 --> 00:01:56,600 Loss of sleep also impairs learning and memory. 34 00:01:56,600 --> 00:01:59,960 So R.J., sleep isn't just necessary for brain development. 35 00:01:59,960 --> 00:02:03,040 It's also critical for body development as well. 36 00:02:03,040 --> 00:02:07,720 As you sleep, chemicals in the brain called hormones are released, which cause your body 37 00:02:07,720 --> 00:02:09,760 to grow and mature. 38 00:02:09,760 --> 00:02:10,760 Whoa. 39 00:02:10,760 --> 00:02:14,480 So if you're saying I sleep more, I'll grow more. 40 00:02:14,480 --> 00:02:15,480 Yes. 41 00:02:15,480 --> 00:02:19,480 The hormones that you release while you sleep are necessary for your growth and development 42 00:02:19,480 --> 00:02:21,200 into an adult. 43 00:02:21,200 --> 00:02:25,920 Other factors that can affect sleep are physical activity, mealtimes, and medicines. 44 00:02:25,920 --> 00:02:31,880 And caffeinated drinks like soda, tea, and coffee can really disrupt sleep. 45 00:02:31,880 --> 00:02:35,400 In addition to getting enough sleep, researchers have discovered that the color of light affects 46 00:02:35,400 --> 00:02:37,440 your biological clock. 47 00:02:37,440 --> 00:02:41,700 We've learned that sleep disruption and exposure to certain wavelengths of light suppress those 48 00:02:41,700 --> 00:02:44,320 important growth and maturation hormones. 49 00:02:44,320 --> 00:02:48,960 R.J., this is one of the machines we use to measure the benefits of the different wavelengths 50 00:02:48,960 --> 00:02:49,960 of light. 51 00:02:49,960 --> 00:02:51,680 Want to check it out? 52 00:02:51,680 --> 00:02:56,360 We found shorter, bluer wavelengths of light, like those we see looking at the Earth's blue 53 00:02:56,360 --> 00:03:01,040 sky, are much more effective for resetting our circadian clock. 54 00:03:01,040 --> 00:03:05,960 Now let's see what a Martian sky is like. 55 00:03:05,960 --> 00:03:13,480 Whoa, this is different. 56 00:03:13,480 --> 00:03:17,920 Longer, redder wavelengths of light, like those in the Martian sky, are less successful 57 00:03:17,920 --> 00:03:20,440 at resetting our circadian clocks. 58 00:03:20,440 --> 00:03:24,960 When we plan for future exploration of Mars, we will need to think about how the biological 59 00:03:24,960 --> 00:03:29,320 clock will respond to the unearthly color of the Martian skies. 60 00:03:29,320 --> 00:03:32,640 Wow, that's a lot to think about. 61 00:03:32,640 --> 00:03:36,480 Our research with the color of light may reveal unknown benefits to us. 62 00:03:36,480 --> 00:03:38,440 But R.J., here's the bottom line. 63 00:03:38,440 --> 00:03:43,720 If you get enough sleep, you'll be more alert, your athletic performance will improve, and 64 00:03:43,720 --> 00:03:46,000 you'll have faster reaction times. 65 00:03:46,000 --> 00:03:50,760 Maintaining a good sleep schedule, eating a healthy, well-balanced diet, and following 66 00:03:50,760 --> 00:03:54,560 an exercise regimen all contribute to better minds and bodies. 67 00:03:54,560 --> 00:03:57,280 They're the three pillars of good health. 68 00:03:57,280 --> 00:04:02,320 You have to have the right ratio between rest and activity to be your best. 69 00:04:02,320 --> 00:04:08,640 For someone your age, that would be a ratio of nine hours of sleep out of a 24-hour day. 70 00:04:08,640 --> 00:04:10,840 R.J., what does your schedule look like? 71 00:04:10,840 --> 00:04:15,000 Well, I get up at 6.30 and try to catch the bus at 8. 72 00:04:15,000 --> 00:04:16,000 Sometimes I'm late for school. 73 00:04:16,000 --> 00:04:19,000 At 8.30, school starts and I'm in the building until 2.30. 74 00:04:19,000 --> 00:04:22,000 Then I go to track practice from 3 to 6. 75 00:04:22,000 --> 00:04:24,000 I rush home, do my homework in my room. 76 00:04:24,000 --> 00:04:29,000 Eat around 8 or so, study some more, and try to go to sleep around 11. 77 00:04:29,000 --> 00:04:33,000 Next day, I'm up at 6.30, and the process begins all over again. 78 00:04:33,000 --> 00:04:34,000 What about weekends? 79 00:04:34,000 --> 00:04:40,000 Well, I stay up late to watch good TV shows, and then I get up about 10.30. 80 00:04:40,000 --> 00:04:43,000 In the afternoon, I might lie around the house to catch up on some rest. 81 00:04:43,000 --> 00:04:45,000 R.J., you're not getting enough sleep. 82 00:04:45,000 --> 00:04:49,000 Could you help me figure out a better schedule that will help me get the sleep I need? 83 00:04:49,000 --> 00:04:52,000 Sure. Let me work on it and get back to you later. 84 00:04:52,000 --> 00:04:55,000 Thanks. Any help you could give me would be appreciated.