For questions pertaining to the physiology and pathophysiology of sleep in humans and animals (e.g., sleep stages and their EEG patterns, sleep disturbances), along with psychological effects of sleep deprivation or fatigue.

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20
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1answer
610 views

Medium-term effects of polyphasic sleep on performance

Typical sleep patterns of one big block of 6 to 9 hours with no naps is usually referred to as monophasic sleep. A second natural sleep pattern is biphasic sleep which breaks up your sleep into two ...
18
votes
1answer
2k views

Is there a reduction of “Brain Fog” with fewer hours of sleep?

I've heard patients who complain of "brain fog" (and fatigue) claim a reduction in "brain fog" (and more mental clarity) when they get fewer hours of sleep (usually less than 5.5 hours). Here I'd ...
17
votes
1answer
2k views

Do people wake up faster with inconsistent alarm sounds?

Many people have one alarm clock sound that wakes them up every morning. Is having this consistent sound the optimal way to wake someone up? Or can you startle someone faster by changing to a ...
15
votes
1answer
379 views

Does dream recall disturb the processes of memory consolidation?

Psychology in the time of Freud was occupied with dreams. Relaying these to one's analyst was an important part of treatment. Fast-forward to less than 100 years later, and we know so much about the ...
15
votes
1answer
899 views

Can you catch up on sleep over the weekend?

The lack of sleep has many negative effects associated with it. Maintained sleep deprivation results in a degraded performance over time (in this case reaction time). Assuming one needs 8 hours of ...
14
votes
3answers
551 views

Why do we always wake up at the climax of our dreams, even when it is an alarm that wakes us?

I know that it probably has something to do with the fact that our dreams didn't really end at the same time our alarm clock rang, our brains just make us think so for some reason.
14
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0answers
300 views

Does dream recall interfere with “reverse learning”? (Crick and Mitchison's theory of REM sleep)

I've recently became aware of the idea of "reverse learning" that might happen during REM sleep - the brain's attempt to eliminate pathological attractors that might appear in neural networks. The ...
13
votes
2answers
346 views

What factors improve mood and increase cognitive functioning when people wake up?

I'm a software engineer doing some research in order to figure out if developing some applications are worth the effort. This work is applied to computational devices including mobile devices and even ...
13
votes
1answer
168 views

How does daily amount of sleep vary within and between healthy adults?

I'm interested in research that has employed the following or similar research design: Measure the daily amount of sleep every day for an for an extended period (e.g., more than a month) in a ...
12
votes
1answer
147 views

Have there been any studies which report a positive correlation between eating certain foods and reported sleep disturbances?

This Skeptics question touched on the subject, but I'm more focused on studies that have been conducted under highly controlled circumstances, like a university sleep lab. We've all heard these old ...
12
votes
1answer
197 views

What defines the easiest time to get out of bed in the morning for humans?

I'm interested in sleep research, and sometimes in conversations with people the following idea gets discussed: "A person becomes aware at a certain time in the morning and feel great(while still in ...
12
votes
0answers
158 views

Do animals that sleep during the day have a different sleep architecture than those who sleep at night?

A typical hypnogram, delineating the sleep architecture for a (human) mammal looks like A distinct distribution of non-REM and REM sleep can be observed. Is this pattern of sleep cycles ...
11
votes
3answers
9k views

Can we smell in dreams?

I'm interested in whether people can smell in their dreams. Do people really experience smell in their dreams? For example, if I dream of smelling a flower, will I feel the smell, too? Is there any ...
11
votes
1answer
287 views

Why do we wake up when we die in our dreams?

A lot of people had some experience with dying in their dreams. They all confirm they remember the whole story until the precise moment of death and it is the death itself what woke them up - not ...
11
votes
1answer
2k views

What is the scientific term for unexpected, spontaneous dream recall?

I'm interested if there's a term for spontaneous dream recall. I will try to define the phenomenon I'm talking about. Over 10 years ago, I started to notice that I can spontaneously recall dreams, ...
11
votes
1answer
141 views

What is the mechanism behind unihemispheric sleep in animals?

It is known that dolphins have the ability to sleep with only one half of their brain at a time. According to this popular science source: Dolphins sleep by resting one half of their brain at a ...
10
votes
2answers
6k views

How is fasting related to insomnia?

Yesterday I started a new diet using intermittent fasting. For this reason I only ate one meal all day. I was pretty surprised how well I passed that day: I studied a lot, did some sports and ...
10
votes
3answers
32k views

Can sleep become addictive?

Can a person become dependent on sleeping (more than they otherwise physically need) in a way that fits the definition of addiction, in the same way some psychology professionals may describe a person ...
10
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2answers
443 views

How long do dreams last?

What is the relationship between time perceived in a dream and time in the external world? Is time running in dreams always faster than the time running in the real world? Is it ratio of real time ...
9
votes
3answers
244 views

What causes dreamers to accept dreams as reality?

I have long had interest in dreaming, and one of the defining features of ordinary dreams is that the dreamer either accepts the dream as "real life", or does not question the surroundings. Compare ...
9
votes
2answers
150 views

What happens in the brain when conscious awareness is changed during dreaming onset?

I've long been interested in dreaming and there's a peculiar phenomenon of the very start of the dreaming process. Different people experience it differently, but even for the same person there's ...
9
votes
1answer
102 views

What is it about the nature of slow-wave sleep that makes it difficult to awaken the sleeper?

In humans, delta wave sleep ("slow wave" sleep, stages III and IV by AASM criteria) is more common in children and becomes only a small percentage of total sleep time in adults. Cortical EEG waves ...
9
votes
1answer
373 views

How are people able to wake themselves up after a pre-specified amount of time?

Auto-suggestion seems to work. Several people I know seem to be able to tell themselves "I'll wake up after 'N' hours/minutes", and do so within a minute or two of that duration. I thought for a ...
8
votes
1answer
281 views

How effective are multiphasic sleep schedules?

Does multiphasic sleep work well enough that it can be used as a replacement for monophasic sleep? Has there been any research done on people that have used bi/polyphasic sleep for extended periods ...
8
votes
2answers
161 views

What is the sleep study that showed that a percentage of humans have a biological clock that is ~28 hours or greater?

There was an article published some years ago about a sleep study (I think from Germany) that showed about 10-20% of people (European's I think) are genetically predisposed to function on a 30-hour* ...
8
votes
1answer
117 views

Why aren't sleep measures consistently measured as mediators/moderators of cognitive performance?

Knowing that sleep quantity and quality affects cognitive performance across many domains, why aren't pre-test sleep measures or intra-test measures of arousal a standard part of all cognitive test ...
8
votes
1answer
184 views

Why is it easier to fall asleep in the dark?

I'm curious if there is any neurological mechanism that explains why falling asleep is easier in the dark. I recognize that this isn't true universally -- a phobia of darkness might make it easier to ...
8
votes
1answer
99 views

What brain regions are activated when a dream is remembered?

Some people remember dreams, others don't. The same person can wake up with dream recall one day and without on other days. I know that the association between REM sleep and dreaming was initially ...
8
votes
0answers
511 views

How much sleep is required to restore maximum cognitive functioning? [closed]

Background: Recently I have really messed up my sleep schedule due to my procrastination. The internet points to some very basic conclusions but I would like to see actual experiments on effects of ...
7
votes
2answers
508 views

Is there a scientific term for when you fall asleep because you can't handle something?

I'm wondering if there is a scientific term that describes when you fall asleep or pass out after some traumatic event? This effect happens when people witness something gruesome (a friend being ...
7
votes
1answer
2k views

Do lucid dream eyemasks work?

There seems to be a few eyemasks available that claim to help the wearer achieve lucid dreaming. For example: The NovaDreamer lucid dream mask works by detecting Rapid Eye Movement (REM) while ...
7
votes
0answers
39 views

Are there any studies that suggest an evolutionary advantage of dreaming?

I've read the answers to this question. But I'd like to ask if, besides those suggested hypothesis, has anyone ever suggested that the advantage of sleeping could be to allow a profound state of rest ...
7
votes
1answer
213 views

Can lucid dreaming detract from the recuperative effect of REM sleep?

Imagine you mastered lucid dreaming, so you have a lucid dream every night. You might want to use this phase to do creative work or problem solving. Would this have a negative influence on the ...
6
votes
2answers
248 views

Are closed eye movements related to the content of dreams or the imagination?

During rem sleep there are observed eye movements, which seem like they would correlate with the person visualizing their dreams. Do their eye movements actually try to follow what they're dreaming ...
6
votes
2answers
172 views

What does daytime actigraphy reveal about an active and awake brain?

I have interest in the study of human motion ( Actigraphy), and have built a couple of smartphone apps using its principles. The apps look at gross motor activity of an individual. Up until now, most ...
6
votes
1answer
428 views

Is learning facts via audio while sleeping possible?

Is there a way to make onself remember facts from an audiobook (containing for instance a list of countries and their capitals) played out loud while sleeping?
6
votes
1answer
114 views

Waking around the same time without an alarm

Anecdotal background I find that regardless of what time I go to bed, or how exhausted I am, I always wake up the next morning between 5 and 6am. This is despite my alarm being consistently set for ...
6
votes
3answers
207 views

How to restore and maintain a healthy sleep pattern?

Background: Some people over holiday periods or weekends get into sleep patterns that involve waking up very late in the day (e.g., 1pm), and then going to bed quite late (e.g.,, 4am). Such people can ...
6
votes
1answer
163 views

Can one incubate on a specific idea in one's sleep?

In this question it is described that intentionally not thinking about a problem can allow the subsonscious to find an answer to the problem; this is known as incubation. I have heard and read it a ...
6
votes
3answers
202 views

Is it possible to induce the processes that occur during sleep such as memory “garbage collection” without actually sleeping?

Some time ago I opened a question comparing drug withdrawal and sleep deprivation symptoms. In fact, my main objective for that question was to know if there was by any chance, a possibility to live ...
6
votes
0answers
87 views

Why do we talk unconsciously while sleeping [closed]

Somniloquy is very fascinating. It is unclear what are the causes, but most of the time it is not seen as a medical condition. "Sleep talking usually occurs by itself and is most often harmless. ...
6
votes
0answers
97 views

Is there difference between a memory of a dream and memory of waking experience?

I'm very interested in dreaming and have pretty good dream recall. This makes me able to recall and distinguish hundreds of experience within my memory and label them as "dreams". I'm trying to ...
6
votes
1answer
110 views

How much additional sleep is required to recover from a given number of hours of sleep deprivation? [duplicate]

A previous question dealt with whether it is possible to catch up on lost sleep. This question is a little different. Assume that a healthy adult has been deprived of sleep for "x" hours. How much ...
5
votes
2answers
1k views

Devices that detect when someone is falling asleep

I'm wondering what types of devices exist that can detect how close someone is to falling asleep. I have heard of several devices that may be able to do this, but I haven't been able to find very ...
5
votes
1answer
100 views

If you sleep during the day, do you need less sleep at night?

If, say, you sleep 2-3 hours during the day (in the afternoon) - Do you need less sleep at night? After all, subjects feel less tired in the evening after sleeping during day. Can sleep hours be ...
5
votes
1answer
131 views

Why would a behaviour effect one sex?

After reading the article Regular sleeping hours really are good for children—if they are girls I started wondering what would be a good explanation for something such as sleep patterns have an affect ...
5
votes
1answer
89 views

Does a short nap improve learning efficiency?

When one attempts to learn a new skill (e.g., play a guitar), it is often heard that the first hour of practice is more effective than the second. I have heard some people say that even 10 minutes of ...
5
votes
1answer
465 views

What is the difference between drug withdrawal and sleep deprivation effects?

Personal sleep-deprivation study: Recently, I posed a question that I'm sure many people find tough already: "Do I really need to sleep?", and so I tested myself, I spent two days without sleeping. ...
5
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0answers
77 views

Why is it so difficult to recall dreams? [duplicate]

You see a dream and wake up during or after it and you remember the dream. Why is it so difficult to remember the dream in the morning, unless you write it down directly when woke up in the night?
4
votes
1answer
478 views

Is it possible to become addicted to sleep deprivation?

Background: After staying awake for an entire night without sleeping medication, some individuals report feeling tired while others report feeling euphoric and at some point begin to hallucinate with ...