Why eyes are closed while we sleep?

Question

Why eyes are closed while we sleep?

Answer 1

Because if they didn't close they would start to dry out being exposed to the air. A friend of mine sometimes sleeps with his eyes open and said they bother him because you don't blink often enough to keep your eyes moist.

Answer 2

Because when your eyes are shut ur eyes don't move as much and you don't think as much so you are much calmer and when you sleep and your brain rests it wants everything to rest. Including your eyes

Answer 3

Sleep is the bodies way of making repairs. If you could not close your eyes the brain would be collecting data that would impair the repairs.

Answer 4

Because if they were open we would be awake.

Well, Our eyes need to be closed in order to go to sleep. If our eyes are opened, we are not able to get the sleep that we need.

If we opened our eyes for 10 hours, they would be dried out and would hurt.

Although we almost always sleep with our eyes closed, people can and do sleep with their eyes open.

Sleep is generally defined by the presence of certain types of electrical activity in the brain. When people are awake, the electrical activity of their brain, as measured by an electroencephalogram, is desynchronized and of low amplitude. As a person enters sleep, the pattern of their brainwaves changes from low amplitude, higher frequency waves to higher amplitude, lower frequency waves. Additionally, sleep is subdivided into different stages. These stages are defined by the frequency and amplitude of the electrical waves being generated by brain activity, and are also related to easily how a person can be aroused by an external stimulus. Finally, there is a separate stage of sleep called rapid eye movement (REM) sleep, which is characterized by a more "awake" looking brain wave pattern, eye movements, and dreaming.

Usually, when we sleep, our eyes are closed. In my view there are 2 primary reasons for this. First, distracting sensory stimuli (lights, noises, etc.) can interfere with sleep, and closing your eyes greatly reduces visual input. Second, closing your eyelids protects your eyes from foreign objects and from drying out during sleep.

That said, there are instances in which people may be asleep with open eyes. One good example is sleepwalking. Usually, a sleepwalker will initially get out of bed and walk around the room with their eyes open. As the episode continues, their behavior can get very complex. They can avoid objects, go to the bathroom, even clean the house. All during this time, an electroencephalogram would indicate that this person is completely asleep. I would imagine you could also see this sort of phenomenon in someone who had been sleep deprived for a long period of time. They might at times appear behaviorally awake when their brain wave patterns are sleep-like.

Answer 5

Because the brain then doesn't have to process what you can see, the mental rate slows, in the first 20 minutes of sleep the brain compensates for this, by producing artificial stimulation (dreams) this is known as R.E.M. (Rapid Eye Movement).

After about 30 minutes the mental rates slows futher, degenerating into N.R.E.M. Stage 1 (Non-R.E.M. where no dreams occur), it then follows cycles through these stages until you wake up.

Once you reach Stage 4, you are in a very deep sleep and difficult to rouse, but whilst you dream in R.E.M. you wake easily, which is why you can generally remember what you were dreaming about.

An image of these cycle patterns can be seen here: http://www.howtowakeupearly.com/img/wake...

Your eyes are also closed because the lids protect them from debris and drying out, by producing tears from the gland behind you eyebrow to keep them moist and in optimum condition.

Hope that helps. :)