The biological process characterized by reversible unconsciousness, unresponsiveness to external stimuli and motor passivity.

learn more… | top users | synonyms

1
vote
2answers
67 views

Does night sleep provide more energy-regain than sleep during the day? [closed]

After reading this, I know that sleeping is an universal function, and that basically everything with a brain has the need to sleep. However, I am still confused to what extent it is necessary to ...
0
votes
0answers
17 views

Relationship between Human Sleep Cycles & Sunlight

What is the relationship between the human sleep cycle and Sunlight? Why do humans tend to sleep for longer hours during the night than the day. Since we rely on Artificial lighting during the night ...
1
vote
0answers
45 views

Rick's gonna die, but why? [closed]

Rick puts his head on the desk in his garage, with the door wide open, and falls asleep until he finally dies. In such a scenario, what would most probably be the cause of death? Why and when? ...
1
vote
0answers
66 views

Why is Melatonin a prescription drug in Denmark while it's sold over the counter in the US [closed]

I read that some countries like Denmark only allow Melatonin to be sold via prescription while other countries like the US or Canada allow it to be sold over the counter. What are the motivations for ...
4
votes
1answer
140 views

Why do we sleep?

While we do know that the human body is regulated by a circadian clock that keeps humans on a sleep/wake cycle, we don’t really know why. Sleep is the time when our bodies repair tissues and perform ...
2
votes
1answer
112 views

How does waking up from an alarm clock work?

During sleep, one's brain is shut down. All it can do is to see some dreams from the semi-conscious mind. Then how does it hear when the alarm clock rings?
0
votes
0answers
17 views

Are there more efficient forms of sleep among mammals?

We know that there are 4 distinct sleep stages among humans and we need about 5 sleep cycles each night. With this in mind, are there mammals that achieve their sleep needs more efficiently? I'm ...
1
vote
0answers
212 views

Why do we generally sleep with our head facing away from the door? [closed]

I am not sure if it is biology, so if it is off please tell me, but it feels so instinctly to sleep away from the door/entrance of the room and feels weird if I am facing to it. I mean I fall asleep ...
1
vote
1answer
109 views

How does the brain manifest and realize the intention to resist sleep?

The question title says it all. What happens in my brain when I resist sleep? I would appreciate explanations on neurotransmitter changes, what areas of the brain activate to resist sleep, what can an ...
3
votes
0answers
487 views

What's the technical difference between fainting (and being unconscious) and falling asleep (and sleeping)?

This is actually a popular question along google results but the answers usually sound like: sleep is voluntary (oh is it?) and healthy fainting is result of accident and is not normal I read ...
3
votes
0answers
37 views

Can body temperature affect the quality of sleep?

If so, how does it influence our sleep? And what can we do to improve the quality of sleep by adjesting our body tempurature?
5
votes
1answer
206 views

Do deaf people sleep better?

Since deaf people can't hear, is relaxing and falling asleep easier for them? In general, do they sleep better than hearing people? Of course some hearing people have no trouble getting to sleep, but ...
2
votes
1answer
78 views

Is the immune system suppressed during sleep?

Of course we have heard that during stress our immune system is suppressed. This leads me to wonder, does the immune system get suppressed when we are sleeping and why? During both these conditions ...
5
votes
0answers
73 views

Why do some medicines induce sleep? [closed]

I have seen lot of people sleep or say that they are feeling sleepy after taking some medicines. Why? I mean, if a medicine acts on some cell of the body because that cell has got its receptors and ...
2
votes
1answer
263 views

Can you recharge without sleeping? [closed]

Sometimes it's difficult falling asleep for almost an entire night. You might feel like getting up and being productive instead, or 'pull an all-nighter'. Or you can try to simply lay in bed to relax ...
2
votes
0answers
51 views

External sensory stimuli that awaken a person from sleep

An external sound or touch can awaken someone. Can a light? It would have to be very strong, but part of the reason might be that it would have to penetrate the eyelids. And can a smell or taste? ...
5
votes
1answer
109 views

Can a lack of sleep degrade balance?

For years, I've noticed that the day after a night of poor sleep (4 hours or less), my balance noticeably degrades. For instance, while walking 20 feet to the coffee maker, I might stumble into the ...
5
votes
1answer
282 views

Influence of eating at late night on sleep

I have often heard the saying that one shouldn't eat a mountain of food because blood will go to the stomach and it'll be difficult to sleep well because the stomach can't rest at night. I see that ...
5
votes
1answer
294 views

Biological origin of shuddering during sleep

What is the biological origin of the following behavior: Sometimes, during the early, formative phase of sleep (when you have a gradually dimming consciousness of what all is happening around), you ...
2
votes
0answers
220 views

Why do body parts sometimes get a itching and tingling feeling when falling asleep?

Just before I fall asleep I sometimes experience an itchy and stinging feeling in my body parts. It can be that the nose or neck suddenly start to itch or a tingling stinging feeling in the legs. ...
3
votes
1answer
102 views

Involuntary twitches and apnoea during early phases of sleep

I assume most people either experienced or have seen people with the following phenomenon: in the early phases of sleep sometimes involuntary twitches occur that usually accompany the pause of ...
8
votes
2answers
200 views

Is it possible for a human to wake up in a wrong way?

There's an old folk saying that goes like "He got out of bed on a wrong foot" - to indicate that the person's day is going poorly because of the way that person woke up. Is it is possible for a human ...
7
votes
1answer
55 views

Behavioral change in dolphins during different hemispheres activity periods?

It is known that dolphins never sleep in the sense that we do, instead they have one hemisphere of the brain sleeping while the other one is awake. I wonder, do they show observable changes in ...
1
vote
0answers
30 views

Immediate Early Genes during sleep

In Neuroscience 3rd ed by Bear et al. on page 607, immediate early genes are described as related to changing synaptic strength, yet have decreased expression during sleep. The explanation given is ...
9
votes
1answer
4k views

What senses are active while sleeping?

During sleep, our body activity decreases. I am wondering on the extent of the lowering of this activity regarding our five senses. Clearly, the sense of touch is still very efficient since shaking a ...
0
votes
1answer
441 views

Is it true that some organs “sleep” at certain times of the day and does this affect dieting or when to take medicine?

Is it true that some organs (such as the liver or the intestines) are less active at certain times of the day, regardless of whether the individual is awake or not?
6
votes
1answer
141 views

Chickens roosting, is it sleep or torpor?

At night when they roost, do chickens experience a state of sleep (meaning do they move from NREM1 to NREM2, NREM3 and REM) or are they in a state of torpor (reduced metabolic rate and decreased ...
1
vote
0answers
37 views

How much does sleeping correlate with daily activity?

I'm a very lazy person. I spend most of my time in a chair, at a computer; I eat more than three meals a day. I don't do any sport, at all. What I want to know is: why do I need to sleep 8-12 hours ...
2
votes
2answers
52 views

awakening effects of light

I tried reading by light from a neighbouring room and felt sleepier than if my own lights were on. Is there a formula for the intensity of light vs physiological preparation for sleep(calcium, ...
5
votes
1answer
236 views

What's the worst that can happen from too much sleep deprivation? Can you die?

It is well known that sleep deprivation causes considerable discomfort in humans (and has even used as a form of torture), but nevertheless there have been people who went through protracted sleep ...
1
vote
1answer
163 views

Does physical exercise following lack of sleep increase the risk of sudden cardiac death (SCD)?

Is there any scientific evidence supporting the hypothesis that physical exercise following lack of sleep increases the risk of sudden cardiac death (SCD)? The only relevant research I could find is: ...
1
vote
0answers
42 views

Dawn simulation - does color change affect waking up?

just curious. Are there any works or research results related to the influence of light color used for dawn simulation? I mean those wake-up lights which try to simulate dawn to make waking up better ...
0
votes
1answer
67 views

What factors affect the likelihood of auditory stimuli causing arousal during sleep?

I've noticed that the sound of water drops makes me wake up from sleep but other more strong sounds don't make me wake up. I can't find anything about this. The only reason I can think of is maybe ...
4
votes
1answer
96 views

What is happening physically when I get sleepy and when I wake up?

After a week of too little sleep, I slept about 12 hours last night to "catch up". It made me wonder: what is happening physically that signals that I'm done sleeping, or conversely, that I need to ...
2
votes
3answers
104 views

Is the quality of sleep dependent on sleep duration?

I've been facing this lately, where I will wake up in the middle of the night after sleeping for perhaps 2-3 hours and be wide awake, but when I go back to sleep, I wake up more tired than before. ...
3
votes
0answers
64 views

TV's so loud when I turn over

Scenario: I'm about to fall asleep with the T.V. on. Having completely forgotten that it was, no longer even hearing it, just before falling asleep I turn over with a 'fresh' ear and it's blaring. If ...
8
votes
2answers
503 views

Why sleep? No, actually, why wake?

I was just reading the sleep threads, and I wondered, why is the body so constructed so that sleep is necessary? (Is it just a design error?) But then, how do things come to be awake at all? How did ...
48
votes
2answers
7k views

Do ants or other insects sleep, and if so why?

I was thinking yesterday about insects (as there was a spider in the house, and I couldn't help but think of anything else, even though they aren't insects), and I started to wonder if ants sleep? ...
9
votes
1answer
181 views

What are the effects of sleep deprivation?

Having recently pulled an "all-nighter" while trying to fix a fatal bug in our release code, I started thinking of any health risks that I might have. What are the adverse effects of staying up for ...
3
votes
1answer
152 views

Does tea have its effect if you have a sleep after drinking it?

If I drink tea, then go to sleep for a while, when I wake up, will the effect of tea still be on me (the refreshing effect)? Does it depend on the duration of sleep?
7
votes
1answer
157 views

Which part of human eyes is getting tired?

It's a thing of common sense that if you read, drive or look at computer screen for too long your eyes will get tired. They burn, itch and try to close all the time. But I was wondering which part(s) ...
3
votes
1answer
318 views

Where do butterflies sleep?

Do butterflies (insects) sleep, and if so, where?? I have googled for information but didn't get an exact answer.
3
votes
0answers
111 views

Is there a correlation between brain size and amount of sleep? [closed]

As far as we know, sleep seems to be the part of the daily cycle when executive functions are resting and memories are fortifying. Many, but not all, of the functions that become dysfunctional upon ...
2
votes
3answers
8k views

Why do our eyes close when we sleep?

Why do our eyes close when we sleep? Is it to relax our eye muscles? How can it be explained from an evolutionary point of view?
4
votes
0answers
97 views

Do invertebrates dream? [closed]

From Wikipedia: Studies have observed dreaming in mammals such as monkeys, dogs, cats, rats, elephants and shrews. There have also been signs of dreaming in birds and reptiles. Have there ...
6
votes
2answers
289 views

How would the human body adjust to sleep times if we were to live in a place with different day lengths?

You sleep at night and are active during the day that's how things work for humans, but theoretically if a human whose parents lived on earth were to be born in another planet resembling earth but the ...
7
votes
1answer
493 views

What causes Paresthesia (Pins and Needles) at a cellular level?

I've looked it up in plenty of places like the Wikipedia page and such, and it is clear that the most common cause of Paresthesia is either a fair amount of pressure on a specific patch of skin ...
3
votes
4answers
428 views

Why do the humans become sleepy after meals?

I don't know about all the mankind, but I know enough people, who becomes sleepy after their meals. Also, I'm not sure, what kind of food do they consume, but I personally get sleepy almost from any ...
4
votes
1answer
236 views

Does playing music during sleep actually suppress rather than rouse the brain?

I've long been interested in the effect of music/sound on dreaming, and even built 2 apps that play music during REM period. Now I'm looking at this article about FMRI studies of a sleeping brain, and ...
1
vote
0answers
40 views

Is there a homeostatic setpoint for number of hours of sleep required by a human?

I've heard this TED.com talk about dieting and it mentions that there's a very definitive setpoint within the human brain about how much a human should weight. The speaker mentions that after as much ...