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I wonder whether the eyes muscle relax when you close them. Common knowledge told us the eyes muscle get tense when you stare at nearby object. If you close your eyes, you eye lids have 0 distance with you eyes. Would the eyes muscle relax in this case?
I would guess that the eye muscle relaxes when the eye is closed. After having the eyes closed, just in the moment after opening them, it seems that the focus is in the distance. It takes a fraction of a second before you can read some text on your computer screen for example . This focusing-duration seems to be shorter when looking into the distance after opening the eyes.
Another effect is when you look at an object in short range for quite a moment and then close your eyes. You can feel the relaxation.
The lateral rectus is a muscle of the eye’s orbit. The main function of this muscle is to pull the pupil away from the midline of the body. The word lateral rectus comes from the Latin latus, meaning “side” and rectus, “straight.” Here is more in-depth information on the lateral rectus muscle:
“The lateral rectus originates at the lateral part of the annulus of Zinn, also known as the annular tendon or common tendinous ring, and inserts into the temporal side of the eyeball. The annulus of Zinn is a tendinous ring that surrounds the optic nerve and serves as the origin for four of the six extraocular muscles, excluding the inferior oblique muscle and superior oblique muscle.” (We got that quote from Wikipedia.)
How Does Our Eye Work?
In the process of seeing, light which is reflected off an object enter the eyes through the cornea.
This thin and transparent shield acts as a guard to protect the inner workings of the eye.
In addition, it helps to refract the light into a round hole called the pupil.
The colored iris will regulate the amount of light passing through by controlling the size of the pupil.
Bigger in the night and smaller in the day.
The rays are then focused further by the lens and travel across the vitreous humor and ultimately reaching the retina.
In the retina, there are millions of tiny light-sensing nerve cells called rods and cones, which are named for their distinct shapes.
In the center, 10% of the retina is called the macula. This is responsible for your sharp vision and detailed vision (color vision too).
When light strikes either the rods or the cones of the retina, it's converted into an electric signal that is relayed to the brain via the optic nerve.
The brain then translates the electrical signals into the images we see.
4. Visual Scanning
After so many hours staring at up-close objects on a screen, help your eyes adjust between objects both near and far. Sit back and observe the room you are in. Find an object at one end of the room and begin to scan the outline of every single thing in the room. For example, start with a television and then move on to the DVD player next to it and then move on the window behind it.
Basically, you want your eyes to be in constant, deliberate motion as you visually take stock of everything around you. You may already think that you are doing this, but most people when working or playing on the computer focus entirely on what is on the screen.
What happens when you shut your eyes too tightly?
Suppose you squint or shut your eyes too tightly, the tensor tympani muscle contracts and tightens the eardrum through a tendon, shifting the stirrup backward from the oval window to the inner ear. This reduces the magnitude of force transmitted to the inner ear and protects it from loud sounds.
It is interesting to note that when muscles contract, vibrations, and low-frequency noises are produced. This is just like when you flex your arm, as you can actually see the muscles in motion/vibration.
You can observe your muscles moving when you flex your arms. (Photo Credit: Ollyy / Shutterstock)
Similarly, when you shut your eyes too tightly, the same thing happens inside your ear. Slow-twitch fibers produce sounds in the frequency range of 10-30 Hertz, while fast-twitch fibers produce 30-70 Hertz sound frequencies (Source). Note that the generally accepted audible range for humans is 20 to 20,000 Hertz, although this audible range may vary depending upon individuals and various environmental factors.
The sound of muscle contractions can be heard directly by flexing a muscle, such as a clenched fist pressed against the ear. Similarly, the sound of a contraction of the tensor tympani muscle can be heard by shutting one&rsquos eyes tightly or enjoying a deep yawn (as jaw muscles are highly tensed when one yawns deeply).
Not everyone can contract their tensor tympani muscle voluntarily (Photo Credit: Flickr)
However, it is important to note that not everyone can produce this rumbling, thunder-like sound in their ears voluntarily by contracting the tensor tympani muscle only a small percentage of people can actually do that. Therefore, don&rsquot keep shutting your eyes tightly in hopes of hearing thunder rumbling in your ears!
Can Simple Eye Exercises Really Improve the Health of Your Eyes?
Many studies have been conducted to find out if eye exercises can improve your physical vision, making it possible to see again without glasses or contact lenses. However, these studies have disproved this myth. Though your eye muscles can be strengthened, your vision will not be improved enough to lose the need for glasses or contacts because “your need for glasses is based on the shape of your eye, the size of your pupil, and the ability to shift focus…” (Dailey, WebMD).
Eye exercises will strengthen weak eye muscles, improving blood circulation and muscle tone. Your eye muscles should be tone in order to achieve the sharpest vision possible, with help from glasses and contacts, if needed. This toning helps to minimize eye strain, allowing your eyes to work more efficiently.
The following are a few eye exercises that can help improve your eyes’ muscle tone:
- Figure Eight: According to Dailey, tracing an imaginary horizontal figure eight with your eyes can slow the progression of myopia, or nearsightedness.
- Eye Circles: While sitting or standing, move your eyes in a clockwise direction 20 times, making the circle as wide as you can. Relax for 10 seconds, then repeat in the opposite direction. Doing this three times daily will help to stretch your eye muscles.
- Focus Shift: Change the focus of both of your eyes by looking at a far-away object for 6 seconds, until it becomes clear. Then, shift your gaze to a close object for 6 seconds, until it becomes clear. Do this exercise repeatedly until your eyes feel slightly tired.
Some exercises are focused specifically for patients with astigmatism in one of both of their eyes. Rebuild Your Vision defines astigmatism as “…the front surface of your cornea not curving the way it should: usually one side will be more flat than the other. Light tries to pass through the cornea but because of the incorrect curving, the light does not pass through evenly and this results in the blurry vision you may be experiencing.”
- A simple exercise to combat your astigmatism involves your head, that’s it! Many people with astigmatism will tilt their head to one side, compensating for one of their eyes. Instead of tilting your head in one direction, try tilting it opposite of what feels comfortable or keep it straight. This exercise will help your brain understand what “straight ahead” truly is.
- Another exercise to help your eyes focus and work together involves a type of focus shift. Without glasses, begin reading text (a book, article, ect.) and then shift your gaze to a different object on the desk (anything other than a line of text). Continue back to the text and keep reading. Switch back and forth until your eyes feel tired, but not strained.
Complete Eye Care’s very own vision therapy specialist, Dr. Hilary Gesford, often incorporates several of these exercises in her office-based vision therapy program for patients. Dr. Gesford specializes in helping kids and adults improve their eye teaming, eye focusing, and eye tracking to alleviate eye strain and headaches and to enhance overall performance in all areas of everyday life.
In conjunction with the correct prescription glasses, eye exercises can strengthen your eye muscles and allow your eyes to be more effective. Also, vitamins such as MacuHealth can help to improve overall eye health and slow or prevent harmful ocular diseases.
Information in this article was obtained through the following resources:
Fromer explained that the retina is the innermost of three tissue layers that make up the eye. The outermost layer, called the sclera, is what gives most of the eyeball its white color. The cornea is also a part of the outer layer.
The middle layer between the retina and sclera is called the choroid. The choroid contains blood vessels that supply the retina with nutrients and oxygen and remove its waste products. [Image Gallery: Eye Implant Restores Some Vision to Blind]
Embedded in the retina are millions of light sensitive cells, which come in two main varieties: rods and cones.
Rods are used for monochrome vision in poor light, while cones are used for color and for the detection of fine detail. Cones are packed into a part of the retina directly behind the retina called the fovea, which is responsible for sharp central vision.
When light strikes either the rods or the cones of the retina, it's converted into an electric signal that is relayed to the brain via the optic nerve. The brain then translates the electrical signals into the images a person sees, Fromer said.
Jake Whalen: Living and Coping with Keratoconus
Jake Whalen is a freelance copywriter who has struggled for most of his life with keratoconus.
Keratoconus is a degenerative condition of the cornea, a transparent dome-shaped tissue that forms the front part of the eye. Keratoconus gradually causes the cornea to thin, bulge/protrude outward, and become cone-shaped. This creates an abnormal curvature of the eye that can cause blurred vision, glare problems, light sensitivity, and even extreme pain.
Learn more about the basics of effective eye care, including:
- The difference between normal eye and vision changes and symptoms of vision problems when you see an eye care specialist.
- Check out our Getting Started Kit for more ideas to help you live well with low vision. to receive free weekly email alerts for more helpful information and tips for everyday living with vision loss.
Aqueous humor is a clear, watery fluid, contained in two chambers behind the cornea, that helps to bring nutrients to the eye tissues. It is produced by the ciliary body, a ring of tissue that sits behind the iris.
As it circulates, the aqueous fluid flows to the front part of the eye, where it is drained by the trabecular meshwork, a sponge-like filtering system located where the cornea and iris meet. After draining through the trabecular meshwork, the aqueous fluid then passes through a small duct, called the canal of Schlemm, and is absorbed into the bloodstream.
The health of your eye depends upon a continuous process of production, flow, and drainage of this aqueous fluid. Any interruption of this process can lead to problems with increased pressure inside the eye, such as glaucoma.
The sclera is a tough white outer coating of fibrous tissue that covers your entire eyeball (all the way around) except for the cornea. The muscles that move the eye are attached to the sclera. The name sclera comes from the Greek word “skleros,” which means “hard.”
The Iris and the Pupil
The iris is a ring-shaped membrane inside the eye that surrounds an opening in the center, called the pupil. The iris contains muscles that allow the pupil to become larger (open up or dilate) and smaller (close up or constrict). The iris regulates the amount of light that enters your eye by adjusting the size of the pupil opening.
In bright light, the iris closes (or constricts) and makes the pupil opening smaller to restrict the amount of light that enters your eye.
In dim light, the iris opens (or dilates) and makes the pupil opening larger to increase the amount of light that enters your eye:
The iris in dim light
In addition, it is the iris that determines your eye color. People with brown eyes have heavily pigmented irises, while people with blue or lighter-colored eyes have irises with less pigment.
The lens is composed of transparent, flexible tissue and is located directly behind the iris and the pupil. It is the second part of your eye, after the cornea, that helps to focus light and images on your retina.
Because the lens is flexible and elastic, it can change its curved shape to focus on objects and people that are either nearby or at a distance. The lens provides 25-35% of your eye’s focusing power.
The ciliary muscles, which are part of the ciliary body, are attached to the lens and contract or release to change the lens shape and curvature.
The lens becomes more rounded to focus on near objects (see Figure 1):
Fig. 1: A more rounded lens can focus on near objects.
The lens becomes more elongated (or stretched) to focus on objects that are far away (see Figure 2):
Fig. 2: A more elongated/stretched lens can focus on far objects
Over time, the lens loses some of its elasticity and therefore loses some of its ability to focus on near objects. This is called presbyopia and explains why people need reading glasses as they become older.
The choroid is a dark brown membrane that is rich with blood vessels, located between the sclera and the retina. It supplies blood and nutrients to the retina and nourishes all of the other structures within the eye.
The vitreous is the jelly-like substance that fills the inside of the back part of the eye. Over time, the vitreous becomes more liquid and can detach from the back part of the eye, which can create floaters. If you notice new floaters or flashing lights, it is important to see your eye doctor, because a detached vitreous can cause a hole (a condition called a macular hole) to develop in the retina.
The Retina and Optic Nerve
The retina is the light-sensitive tissue that lines the inside surface of the eye, much like wallpaper. Cells in the retina convert incoming light into electrical impulses. These electrical impulses are carried by the optic nerve (which resembles your television cable) to the brain, which finally interprets them as visual images.
The macula is the small sensitive area in the center of the retina that provides clear central vision. The fovea is located in the center of the macula and provides the sharpest detail vision.
8 Fascinating (but Quite Creepy) Things That Happen to Your Body When You Die
We&rsquore hooked on murder- and death-obsessed shows like How to Get Away with Murder (who killed *******?!) and The Walking Dead (the zombie makeup is on-point), but most of us know very little about what actually happens to us when we die. After all, who really likes to think about kicking the can?
Some of the things that your body does in the hours after your final heartbeat are pretty cool (albeit in a slightly morbid way). Read on to learn what your body does when it doesn&rsquot have relationship drama, workouts, or even breathing to deal with.
1. Your Hair and Nails Look Like They Grow
Have you heard that hair and nails keep growing in a casket? Well, they don&rsquot, although it sure can look that way. Once you&rsquove kicked the bucket, your skin dries out, so it shrinks away from your cuticles and hair follicles, making your nails and hair appear longer than they were when you were alive and well, explains Robert D. Webster, author of Does This Mean You'll See Me Naked? Field Notes from a Funeral Director.
2. Your Body Gets Rock Hard
&ldquoRigor mortis, or stiffening of the muscles after death, occurs from depletion of adenosine triphosphate (ATP), the chemical in our muscles necessary for relaxation of the muscle fibers after a contraction,&rdquo says Judy Melinek, M.D., a forensic pathologist and co-author of Working Stiff: Two Years, 262 Bodies, and the Making of a Medical Examiner. &ldquoATP is produced metabolically by muscle cells and forces your muscle&rsquos contractile units to disengage. When you stop breathing, your cells stop producing ATP. The microscopic fibers lock up, and your muscles stiffen.&rdquo
This sets into your face within two to four hours after death and hits your bigger muscle groups in about six to 12. &ldquoThis is not like a tense muscle cramp after a marathon, this is epic hard,&rdquo says Jeff Jorgenson, director of eco-friendly funeral home Elemental Cremation and Burial in Seattle. After a day or two, those muscles start to degrade, and the body looks more relaxed.
3. You May Poop and Pee Your Pants
While rigor mortis sets in eventually, as soon as you die, every muscle in your body relaxes. That includes the sphincters that are in charge of keeping your bladder and bowels on lockdown, says Jorgenson. So if there is anything to expel, it could possibly seep out. &ldquoWe aren&rsquot talking about the biggest dump these people have ever taken, though,&rdquo he says. After all, the muscles that are responsible for forcefully pushing out the nasties are dead.
4. Your Wrinkles Disappear Immediately
Here&rsquos one we actually like. Since your muscles lose all tension the moment you die, they stop pulling on your forehead, creating those worry lines you hate so much, says Jorgenson. Essentially, it&rsquos the same reason Botox works. If you&rsquore really old, saggy skin may still be an issue, but at least your forehead won&rsquot be scrunched.
5. You May Moan and Groan
Just because you&rsquore dead doesn&rsquot mean there isn&rsquot any air in your lungs. If someone applies some force to the chest, say, by moving or rolling your body, some air can come up your windpipe, rattle your vocal chords, and produce a moaning, groaning, sighing, or squeaking sound, says Jorgenson. While legends of bodies randomly blabbering are common, no sound is going to come out of your mouth unless something is pushing it out.
6. Some of Your Body Parts Keep Living
For a little while, at least. &ldquoAs soon as you stop breathing and your heart stops beating, your organs start to die," says Melinek. "However, all the cells don&rsquot die immediately, and there is a window that allows for you to be resuscitated and remain intact&mdashand an even larger window that allows for organ and tissue transplantation." To donate organs such as your heart or lungs, something has to breathe for you until after the doctors have removed the organs, but you can donate tissues such as your corneas, skin, bone marrow, and even heart valves even 15 hours after your last breath. Learn how to become an organ donor.
7. Your Skin Gets Stained
You know how in TV shows, fake blood pools around bodies and looks a little like JELL-O? The same jellification happens to the blood in your body. Without your heart keeping the blood flowing, gravity takes control and it pools and thickens in whichever one of your body parts is the lowest, says Webster. If you&rsquore sitting down, that might be your feet and ankles. Or if you&rsquore lying on your back, your booty. If the blood stays there for 12 hours or longer, it will permanently discolor the skin.
Myopia Prevention and Control
"Eye exercises" is commonly used to describe non-prescribed, non-doctor-directed activities for vision correction. "Vision training" is commonly used to describe prescribed, doctor-directed activities for vision correction. The thought by some is that muscles of the eye are responsible for the development of myopia and that by either strengthening, relaxing or better coordinating these muscles that myopia can be prevented, controlled or eliminated.
How do Eye Exercises work for myopia control?
Because of the confusion over what eye exercises means, one has to be specific about the actual type of treatment. The shortest answer is that there is no credible evidence that exercises work to control myopia but there are valid reasons to suspect that prescribed vision training for one type of myopia holds some promise of benefit. This type of myopia is where an individual has a tendency to cross their eyes slightly when reading (they don't actually cross) AND where the eyes don't fully focus on the book but rather further away, behind the book, something called a lag of accommodation. You can read about the research in the Research menu under the "Accommodation (focusing)" topic. Your doctor is the only one who can determine if you meet these criteria and might benefit from directed vision training.
Because "exercises" often seems to imply a non-prescription treatment with no doctor involvement, the idea of exercises to treat myopia has a large following in the alternative lifestyle press. There are volumes of testimonials available from people who say their eyes got better or from people offering to sell programs of exercises designed to do the same. Read more about these ideas under Pseudo Science in the Treatments menu.
People can get used to blurred vision and they can become better at guessing at blurred letters. For some that is enough "proof" that their eyes improved. Scientists measure myopia by where the light focuses in the eye and the length of the eyeball. Identifying letters on an eye chart is a secondary method that is quite variable between different patients with normal vision.
What are exercises for myopia prevention?
The eye has six large external muscles that control where the eye is aimed. Coordination of the muscles between the two eyes is important to avoid double vision and eyestrain. You don't want your left eye looking left while your right eye looks up. The eye also has a smaller internal muscle that controls the distance at which the eye is focused. This ciliary muscle can either activate (perform work) and focus the eye on objects nearby, or it can relax to focus on objects further away. The muscle is attached to and changes the shape of the lens in the eye to change the eye's focus. As a person ages, the lens loses elasticity (just like skin which ages and loses elasticity resulting in wrinkles) and the now older, more rigid lens will not reshape itself for different distances. At that point, usually in a person's forties, reading glasses become necessary.
It helps to understand how the focusing muscle works. The muscle is attached to the lens by fibers, essentially strings. The ciliary muscle is a circular muscle with the lens in the middle of the circle. Imagine a water balloon with a circle of strings attached to an outer ring, the ciliary muscle. If the ring of muscle activates, it makes the opening smaller. This relaxes the strings attached to the lens in the center and the lens is free to bulge large under its own elasticity, just like a water balloon. If the muscle relaxes, making the opening larger, the strings are pulled tighter and the lens is pulled against its elasticity into a flatter shape that allows for distance vision.
Most "exercises" described as helping myopia in the alternative press are actually relaxation techniques, or perhaps flexibility techniques. A common exercise would be to roll your eyes in a circle. There is no problem with that by itself. Some people do have restricted muscle actions, but it is generally the more elderly population, not the age group concerned about myopic progression. Other exercises work to relax the real focusing muscle, the ciliary muscle. The idea is that if the ciliary muscle can be relaxed enough, the eye should return to distance focus as the lens is pulled flatter. Thus directions for myopia control in the popular press will be along the lines of "Close your eyes, hold your warm hands over your eyes and imagine you can see pure black." The only problem is that myopia is caused by the eye being too long for the relaxed muscle. If relaxing the muscle creates an improvement in vision, the person wasn't that nearsighted to begin with. That is why doctors use various techniques to determine if the ciliary body is not releasing its full focus, often including the use of special eye drops that numb the muscle (a procedure called cycloplegia) so a determination of the true amount of myopia can be determined without interference from the muscle.
It is possible to cramp the muscle by overworking it for near vision tasks, such as long periods of time focused on objects very close. This is called pseudo myopia and is sometimes noticeable at the end of the day when distance vision is more blurred but is clear by morning or perhaps just blurred all the time. Relaxation techniques, vision therapy or eye exercises might work in these situations to relax the muscle but there has been no study to show that pseudo-myopia, if not treated, leads to more myopia. Sometimes glasses are prescribed to try and prevent the condition by wearing a different prescription (reading glasses) with the goal of preventing the cramping from occurring. No study has been done to show any decrease in myopic progression when prescribing glasses for pseudo myopia. At the same time, there is no harm in relaxation. Studies would suggest that prescribing directly for pseudo-myopia, in effect over prescribing of power, should lead to more myopic progression, but no study has tested that theory either.
Several studies have shown that something called "lag of accommodation" is greater for people with myopia. Accommodation is the term used to indicate muscle activated focusing of the eye for near distances. It is possible to measure how accurately a person is doing this focus. The most common situation is that a person will "lag" or under-focus for the distance being viewed. Thus if the book is 18 inches away, a person may lag their focus so that their eyes are actually in focus at perhaps 22 inches, close enough to read the text but not the sharpest focus. Some exercises are aimed to make this activity more accurate with the goal of reducing feelings of eyestrain or even to prevent the progression of nearsightedness. Studies differ on the meaning of this lag. Some indicate that treating the lag will slow progression and some have shown that the lag does not seem to be predictive of future myopia but rather a result of myopia that has already developed. It may be that the lag is an indicator who will actually benefit from treatment, not who will eventually develop myopia.
Are there any side effects?
The main risk is that after significant investments of time and money you find yourself still nearsighted and continuing to become more nearsighted.
Here&rsquos Why Your Eye Is Twitching&mdashand How to Make It Go Away
Wondering what it means when your eye twitches? Although annoying, the good news is that eye twitching is rarely serious.
A twitch in your eye can be incredibly irritating and distracting. But luckily, eye twitch is usually not painful, and very rarely is it cause for concern. "Basically it’s an overstimulation of the eye muscles," says Donny Suh, MD, associate professor at the Truhlsen Eye Institute of the University of Nebraska Medical Center in Omaha. This overstimulation results in an involuntary contraction of the muscles, which manifests as that small twitch or tic in your eye. Here, what you need to know about eye twitch, and what you can do to make it go away.
What causes eye twitching
There are a few possible eye twitch causes, and most of them are easily remedied. Two of the most common? Stress and lack of sleep. Too much caffeine, alcohol, or nicotine can also lead to eye twitching.
An eye twitch can also be triggered by dry eye, which can itself be caused by a number of different factors."It can be [caused by] an autoimmune disease, but more commonly it occurs with aging or medications," says Dr. Suh. Antihistamines, antidepressants, and nasal decongestants are common culprits.
Eye twitch may also be a symptom of certain eye conditions, including glaucoma, blepharitis (an inflammation of the eyelids), uveitis (another type of eye inflammation), or a corneal abrasion.
When to see a doctor
"Twitches are typically benign and should only last for a few weeks," says Dr. Suh, adding that a lingering eye twitch could actually lead to more anxiety, which prevents it from going away. "The problem is that once you develop these twitches, they tend to cause a vicious cycle."
However, if an eye twitch lingers for a long time, or if you have double vision, a pupil that becomes irregular-looking, or facial contractions outside of the eyelid, Dr. Suh recommends seeing a specialist right away. In very rare cases, eye twitching can be an early sign of a more serious condition, including Bell&aposs palsy, multiple sclerosis (MS), or Tourette syndrome.
How to stop eye twitching
Lifestyle changes can often remedy an eye twitch, but it&aposs helpful to pinpoint the exact cause. If you suspect that stress or fatigue is to blame, make sure you get plenty of shut-eye, practice good sleep hygiene, and try relaxation techniques (such as meditation or yoga). Limiting your consumption of caffeine and alcohol (or abstaining completely) could also make a difference. If the twitch is related to dry eye, over-the-counter artificial tears may help ease symptoms.
Dr. Suh also stresses the importance of limiting the amount of time you spend looking at electronic screens. He recommends giving your eyes a rest every 10 minutes. To relax the eye muscles, close your eyes briefly, then look at a distant object. You should take similar breaks when reading books, or any time you’re focusing your eyes intensely.
"This would just take 10 to 15 seconds, so having no time is not a good excuse," says Dr. Suh.