If we're able to get less good sleep as we age, and sleep is essential for mental acuity (forming memories, etc) and for physical health (growth hormone, etc), i've long wondered if the two are related.
Some of them say sleep has something to do with maintaining a plausible number of neuronal connections (synapses) in your brain: the more you learn and do during the day, the more synapses you build, the more sleep you need to clean up for the next day. As you age, your brain plasticity decreases, i.e. the ability for your brain to change the number of synapses is not as good. This is why you might need less sleep than when you were a young kid.
If you are interested in the topic, I'd suggest to have a look here: http://thesciencenetwork.org/programs/waking-up-to-sleep Some of the talks can be of interest to the general reader. The Science Network is a very good source of good-quality easy to access scientific material.
Is screwing with my sleep cycle a bad idea at this age? Or is age irrelevant? Biphasic sleep especially sounds attractive to me, but I do not know whether it would be healthy to try.
Given that you are a sleep researcher, I was hoping perhaps you could provide some insight?
At your age your sleep pattern is already pretty much messed up by itself (you may already find yourself working late at night and having big sleep inertia in the morning) and I wouldn't complicate things any further.
There was a kid exactly your age who in 1964 decided to establish the world record for sleep deprivation. http://en.wikipedia.org/wiki/Randy_Gardner_(record_holder) He went on for 11 days and he was supported by a physician all the time. This was back in the days when we still didn't know sleep deprivation was lethal in rats.
I thought it was clear from looking at other animals that a large part of the value of sleep relates to saving energy. Animals that do something like sleep while staying awake burn more energy but don't drown / get eaten as much which makes up for that. Granted, there is other things that happen as part of sleep, but saying we have no idea when some things are fairly well known seems to be over the top.
After centuries of interest we still don't know why we sleep. We have no idea, really. We know rats die if you sleep deprive them for long enough (between 10-30 days) but we don't know what they die of. I work with fruitflies myself and investigating sleep function is what I am trying to do.
The human body saves a lot more energy than one frankfurter bun though sleep by simply not moving all that much. Clearly the brain and body are doing something useful while you sleep, but if it needs to do that stuff and walk around / be awake at the same time it would use even more energy.
Bats, sleep 18-20 hours per day vs. giraffes which sleep 3-4 hours per day etc.
PS: REM sleep is another issue, but the differences in human sleep cycles suggest that sleeping less is not the only goal.
I see. I think what you are talking about is not even energy expenditure but what we call "the null hypothesis". Basically says that there might be no other active function than sleep other than resting as a mean to escape predators and not using energy. This is far from being the accepted hypothesis on sleep function: in fact there is basically only one guy who still talks about this (Jerome Siegel, UCLA); the rest of the community is pretty much convinced that this is not the case. I'd suggest you reading this on the matter: http://www.plosbiology.org/article/info:doi/10.1371/journal.... (it is open access).
PS: Your liver does many things necessary for you to live. It also does many things that help you live a better life. Talking about what your liver or sleep does, without including the useful side effects is not the full story. Sleep deprivation hinders memory formation in humans and hinders reaction times. Are those related to the core function of sleep or just a codependence developed due to other useful features of sleep? I don’t think there is a clear separation between the two.
Edit: I can't read that link.
I, myself, have nothing much to add in the way of hard facts, but using logic, I think that sleep-as-an-energy-saver seems off. Sleep seems like a highly vulnerable state for early animals. If the only initial benefit of sleep was energy conservation, it seems like animals that simply chose to rest would have an edge upon those that slept. By resting, they'd conserve the same energy, but would stay alert and responsive.
And it interests me that animals that cannot rest (sharks, for example) still sleep.