AMELIA: Matt, I was asleep. You know you're supposed to knock?
MATT: What are you doing?
AMELIA: BTN Investigates! I'm the investigator. Mitchell and Troy would like to know why we sleep.
MATT: Where did you get that magnifying glass from?
AMELIA: Nowhere.
MATT: I like that jacket.
AMELIA: I haven't got time for this! I have investigating to do!
MATT: Have we done this before?
Sleeping! We spend about one third of our lives doing it! But besides the odd memory of a dream here or there, most of us are in the dark about what actually happens after we close our eyes. One thing you might already know is that we need sleep like we need food and water.
CARL: Sorry, Amelia, I just can't sleep with you watching me. It's just really weird.
AMELIA: But, Carl if you don’t sleep you might die.
Studies show that animals which are deprived of sleep for a long time can have seizures and can actually die from exhaustion. In theory, the same goes for humans. In fact, sleep is so important that humans and other animals actually risk danger to do it. When we're asleep, we're almost completely unaware of our surroundings. That isn't such a problem now, but a long, long time ago, we could've been attacked by wild animals! Even now, sleeping animals are more likely to be attacked by predators. That's why some animals, like dolphins, have found clever ways to do it. They only sleep with one half of their brain at a time. That means they can still come up for air and swim along using only the half of their brain that's still awake!
But we can't all be dolphins, so I've decided to see if a real sleep investigator can shed some light on the mysteries of human sleep.
AMELIA: So Charlotte, why do we sleep?
CHARLOTTE GUPTA, PHD STUDENT Well, there's not really a clear, simple answer I can give you on that, sorry.
AMELIA: Really? Well, sorry Mitchell and Troy, I guess there are some questions you just can't be answered.
CHARLOTTE GUPTA, PHD STUDENT: Hang on, hang on, there’s some things that we do know about sleep. A lot of people thought that sleep was something where our bodies aren't doing anything, almost like we were unconscious during the night, but now we know that there's a lot that our brain does when we're asleep and it’s really busy working through a lot of things so that we're prepared for the next day.
One idea is that our brain uses a bit of shut eye to recharge parts of it that are constantly working, like this area called the prefrontal cortex. It helps us plan and make decisions. But even when we're super relaxed, it doesn't stop. Like have you ever tried thinking about nothing? You end up thinking about thinking about nothing, right? So some experts reckon sleep is the only time this part can restart. Our brains are also busy cleaning out old stuff, making space for new stuff, and sorting through memories as we sleep.
CHARLOTTE GUPTA, PHD STUDENT: So there's a lot that we take in during the day when we're at school we're learning different things, we're seeing different things so during the night one theory is that our brain is sorting through all of that information and going through and working out what's important and then it stores that information as memories and when we wake up we can remember what we've learnt the day before.
It is proven that people who don't get enough sleep struggle to learn new information, whereas a good night's sleep can help us be more creative and solve problems. So even though scientists don't know exactly why we sleep yet, it's a good bet that it has a lot to do with stuff going on inside our heads!
AMELIA: Matt, you're still here.
MATT: Yeah. Since when did you have an office?
