-
Asked by griffmeg11 to Clare, Mariana, Pedro, Robert, Susanne on 13 Nov 2012.
-
Mariana Campos answered on 13 Nov 2012:
Hey griffmeg11,
This is because we have an internal clock that is adjusted according to the light/dark cycles. Almost all living creatures have this clocks that is called circadian rhythm. This affects many things like your brain activity, hormone levels, etc. Darkness increases the production of one of those hormones called melatonin. This usually peaks at night at makes you more sleepy.
-
-
Robert Insall answered on 13 Nov 2012:
Good question, @griffmeg. Mariana’s answer is a good one, too. Look at “circadian clock” in wikipedia for more info.
I have a sneaking suspicion my melatonin and circadian rhythms aren’t set quite right. I hate mornings and work slowly. In the evenings I work fast and think well and I never want to go to bed on time. When I was doing my PhD and freed from other peoples’ time constraints I worked on a 26 hour day – woke up 2 hours later every morning (afternoon) and went to bed later every night…
-
Clare Taylor answered on 13 Nov 2012:
Mariana explains it perfectly! But did you know that a lot of what we know about circadian rhythms has come from the study of hamsters? Hamsters sleep during the day and are awake during the night – the opposite to us! I know because sometimes when I am awake during the night I can hear my hamster running on her wheel!
If you have ever been on holiday to somewhere far away like America or Australia, your circadian rhythm get’s a bit confused because of the difference in time zone – this is called jet lag! I visited Australia this summer and my sleep patterns were a right mess for the first few days because their clock was 9 hours ahead of ours. My body wanted to sleep at the wrong time of day although my brain could tell that it was the wrong time – when it was 10 pm by my body clock time, it was actually 7 am the next morning by Oz time, and when it was 10 pm Oz time, it was 1 pm body clock time! My brain and body were very confused for a few days until my brain got used to the different time and the difference in light, because it is light that sets our body clock.
In fact, light is really important to us – having a good rhythm is important for our health and well-being and is why some people are grumpier during the winter! In some cases, people have an extreme reaction during the winter and suffer from something called seasonal affected disorder (SAD) because of the lack of natural light. This can be treated with light therapy and people can also be given melatonin to help them adjust.
-
Susanne Muekusch answered on 13 Nov 2012:
hi griffmeg11,
everything has been said, i just want to add that I like your questions. Asking good questions is the first step to being a good scientist!
Comments