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How does sleep prevent our eyes from drying out?


If we don't sleep for about 16 hours, our eyes start to get dry, and no amount of eye drops helps. You use eye drops and then you're dry 10 minutes later.

However, after you've slept for 8 hours, your eyes can go another 16 or so hours without drying out.

What specifically happens to our eyes during sleep that prevents them from drying out in the next 16 hours after sleep?

Are there any research papers explaining the mechanics of all this?

The reason I am asking about this is in order to understand whether there are any connections between nasal and eye moisturization.

There's a condition called empty nose syndrome, in which people with reduced nasal turbinates suffer from a range of symptoms and a lot of them have to do with their nose getting dry.

Here's a CT scan of a person suffering from empty nose syndrome in one nostril. As you can see, one of their turbinates has been reduced, and the other one looks normal.

There's something called "the nasal cycle", it's a phenomenon where turbinates swell up on one side at a time in order to "rest", according to wikipedia. Here's a picture illustrating the nasal cycle:

As you can see from the picture, one nostril of this person is mostly closed, due to cavernous tissue being swollen. It is not a disease, it is actually how our nose normally works.

Of course, if you have reduced nasal turbinates, like in the first picture, it is impossible to properly close the nasal airway and expect it to "rest", so that it can start producing moisture again.

Does that mean that our nasal turbinates work in the same way as our eyes do? They have to be closed for a while in order to properly produce moisture?

As I've mentioned before, when your eyes are dry, you can moisturize them, and then they're dry 10 minutes later… It seems to be the same with empty nose syndrome patients. It seems to me that in order to restore normal moisture in the nose we need to have it closed for several hours. I think it is so, but I'd like to first find out why our eyes need to be closed in order to rest. So, I want to find the parallels between nasal and eye moisturization.


Stop wishing, start doing!

If I had to apply for university or work I would choose my best oral and written evidence, which are:

Written evidence:
http://angelinawurth.blogspot.com.es/2015/03/australia.html
Oral evidence:
https://audioboom.com/boos/2985878-nip-tuck-dialogue

I have choosen these evidence because I think that they show the best my English level and my personal life, my goals, hopes and my personality.
Firstly, the written evidence is divided in paragraphs linked with discourse markers and correct puntuation signs. I haven't used the same vocabulary and I tried to use some different connectors (Plus, due to. ). I was very inspired when I wrote it and I was a little bit confused about my future, so I just let go all my feelings go into it. In conclusion, I decided to choose this post because it exposes my plans for the future and my goals.
Secondly, the oral evidence demonstrates my pronunciation and fluency while speaking English.

To sum up, I don't consider that these evidences shows my best level because I know that now after reading it another time there are a few things I would change, like the structure, some vocabulary, connectors.


Eyes send an unexpected signal to the brain

Retinal section from a mouse where cell nuclei are labeled in blue, inhibitory cells are labeled with magenta, and ipRGCs are labeled in green. Credit: Northwestern University

For decades, biology textbooks have stated that eyes communicate with the brain exclusively through one type of signaling pathway. But a new discovery shows that some retinal neurons take a road less traveled.

New research, led by Northwestern University, has found that a subset of retinal neurons sends inhibitory signals to the brain. Before, researchers believed the eye only sends excitatory signals. (Simply put: Excitatory signaling makes neurons to fire more inhibitory signaling makes neurons to fire less.)

The Northwestern researchers also found that this subset of retinal neurons is involved in subconscious behaviors, such as synchronization of circadian rhythms to light/dark cycles and pupil constriction to intense bright lights. By better understanding how these neurons function, researchers can explore new pathways by which light influences our behavior.

"These inhibitory signals prevent our circadian clock from resetting to dim light and prevent pupil constriction in low light, both of which are adaptive for proper vision and daily function," said Northwestern's Tiffany Schmidt, who led the research. "We think that our results provide a mechanism for understanding why our eye is so exquisitely sensitive to light, but our subconscious behaviors are comparatively insensitive to light."

Image from a mouse retinal section where cell nuclei are labeled in blue, RNA for the GABA synthesis enzyme Gad2 is labeled in magenta, and RNA for melanopsin is labeled in green. Credit: Northwestern University

The research will be published in the May 1 issue of the journal Science.

Schmidt is an assistant professor of neurobiology at Northwestern's Weinberg College of Arts and Sciences. Takuma Sonoda, a former Ph.D. student in the Northwestern University Interdepartmental Neuroscience program, is the paper's first author.

To conduct the study, Schmidt and her team blocked the retinal neurons responsible for inhibitory signaling in a mouse model. When this signal was blocked, dim light was more effective at shifting the mice's circadian rhythms.

"This suggests that there is a signal from the eye that actively inhibits circadian rhythms realignment when environmental light changes, which was unexpected," Schmidt said. "This makes some sense, however, because you do not want to adjust your body's entire clock for minor perturbations in the environmental light/dark cycle, you only want this massive adjustment to take place if the change in lighting is robust."

Schmidt's team also found that, when the inhibitory signals from the eye were blocked, mice's pupils were much more sensitive to light.

"Our working hypothesis is that this mechanism keeps pupils from constricting in very low light," Sonoda said. "This increases the amount of light hitting your retina, and makes it easier to see in low light conditions. This mechanism explains, in least part, why your pupils avoid constricting until bright light intensifies."


How to Get Rid of a Red Eye

This article was medically reviewed by Albert Chang, OD. Dr. Chang is an Optometrist at the Family EyeCare Center in Campbell, California. He graduated from the Southern California College of Optometry in 2015. He has interests in diagnosing and managing ocular disease, including diabetic retinal disease, glaucoma, and macular degeneration.

There are 14 references cited in this article, which can be found at the bottom of the page.

This article has been viewed 1,137,365 times.

Have you ever looked in a mirror and noticed that your eyes were red? Whether you've been staring at a computer or TV screen for too long or are suffering from allergies, red eyes can be painful and ugly. Fortunately, there are many ways to reduce the irritation and swelling. Eye redness can go hand-in-hand with dry eyes, so some treatments address both issues. Other problems such as infections, inflammation, ocular trauma, or a foreign body can cause redness. At those times, it is best to seek medical attention.


32. Your Epigenome Needs Sleep, Too!

Imagine that you are a college student, whose professors all magically decided to give exams and projects due on the same date. For some reason, you procrastinated until the last minute, and now you need to pull an all-nighter at the library. You begrudgingly head to the fourth floor of the library, prepared to stay awake with a bag full of your favorite candy bars and snacks, a Venti Starbucks iced coffee, and a couple cans of Red Bull. You finally leave the library with sleepy eyes just as the sun slowly rises above the horizon. On the actual exam, you feel very tired and have trouble concentrating. A couple days later, you get your not-so-great grade back for your exams and projects, and you make a promise to yourself that you will never make the same mistake. But two weeks later, you end up doing it again a couple weeks later. This all sounds too familiar, right?

Well, just like in this hypothetical situation, if you have ever pulled an all-nighter in high school or college, or just had a restless night, you have probably also noticed how foggy your brain feels the next day. Even after that cup of joe or Red Bull, everything feels a little bit slower, a little bit harder to understand and remember. As you take notes in class, something just seems off, and it does not feel like you are truly processing anything that is coming out of your professor’s mouth or the hot gossip your friend is sharing next to you. This is not all in your head. In fact, your actual brain is not processing quite as quickly or making nearly as many connections on a cellular level.

Sleep is an integral part of daily functioning for everyone. The reason why you feel so sluggish after an all-nighter is because sleep deprivation disrupts cognitive functions, including learning and memory, and has a profound impact on the molecular biology of the brain. This is especially true of the epigenome, which encompasses all of the proteins and other factors connected to your DNA that help control which genes are turned on and off. What makes the epigenome so special is that it is regulated by external factors (such as how much sleep you have had) and is able to affect gene expression without actually changing the sequence of your DNA.

To truly be able to understand the mind boggling world of neuroepigenetics and how sleep, or lack thereof, impacts the epigenome, one first has to understand the basics of gene expression and what epigenetics actually is. Consider the quizzes you used to take in magazines where the answer to every question led to a new set of questions based on your answer until you reached a final outcome. They were like a map where each decision had an impact on the next leg of your journey. The same idea can be used to understand epigenetics. Each decision you make about your external environment can have an impact on the internal mechanisms in your body. If DNA is the instructional manual to build genes, and genes help regulate important decisions in your body, then your decisions about what you do to your body serve as the toggle to the switch that determines which processes are turned on and which processes are turned off.

In both human and animal models, the relationship between sleep deprivation and the epigenome has been widely studied. In part, the importance of the neuroepigenome – the epigenome of the brain and the nervous system – is highlighted by evidence linking it to changes in the physiology of the brain. The epigenome plays a critical role in regulating gene expression responsible for memory storage and synaptic plasticity, both of which determine the brain’s capacity for adapting to experiences. This role is further backed by the synaptic homeostasis hypothesis, which explains our innate need for sleep in order to maintain healthy neuronal connections and prevent our brains from descending into a general state of chaos. The hippocampus, which is the portion of the brain responsible for memory and learning, is shown to be especially sensitive to sleep loss. Changes in behavior observed from experiments involving sleep and the hippocampus are a result of genetic and physiological changes, further cementing the involvement of neuroepigenetic mechanisms. Sleep loss has also been shown to disrupt metabolic and hormonal regulation and increase the risk of obesity, and this link between sleep and brain integrity and activity can be seen with a variety of brain imaging technologies.

When it comes to sleep, how much sleep you are getting may be impacted by a number of factors such as your work, your lifestyle, stimulants you may be taking, and other health conditions. Whatever the reason, if you are not receiving enough sleep, the deprivation can result in a number of internal changes within the gene that can impact your ability to function.

Mechanistic Changes

As you go through your quiz, the answers you provide about your sleeping habits can toggle three different kinds of switches in your epigenome: (1) DNA methylation, (2) histone modification, and (3) non-coding RNA molecules. These mechanisms can function on their own to change gene expression, or in some cases may work together to cause changes in phenotypic expression – in other words, the changes in behavior or physiology you may be experiencing.

Figure 1. The Influence of Sleep on Gene Expression

Gaine, M. E., Chatterjee, S., & Abel, T. (2018). Sleep deprivation and the epigenome. Frontiers in Neural Circuits, 12, 14. https://doi.org/10.3389/fncir.2018.00014

DNA Methylation

The most common change that occurs is DNA methylation. This toggle switch works by enabling addition of a small molecular tag known as a methyl group (-CH 3 ) to the nucleotides that make up DNA. It is most often added to a dinucleotide sequence composed of a cytosine and a guanine connected by a phosphate (termed CpG). While the brain needs a certain number of these tags to function properly, when you do not get enough sleep, your body often starts to attach too many of these tags to the CpG complexes within your genes resulting in a process called hypermethylation. A class of molecules used to regulate DNA methylation called DNA methyltransferases (DNMTs) starts overexpressing, which in turn functions to reduce gene expression by calling upon a repressor molecule known as methyl-CpG binding protein 2 (MeCP2) to stop the gene from transcribing molecules important for essential functioning. Because many of these molecules are necessary for brain function, studies show that disrupting the normal level of DNA methylation through lack of sleep can impair neurological function as well as biological.

Histone Modification

Another common epigenetic change that acts as a toggle switch is histone modification. Histones are proteins that help package DNA into a more compact form. How tightly DNA wraps around the histones changes how much DNA is available to be expressed and therefore controls the degree of gene expression. The relationship functions much like a spool of thread — how tightly the thread is wrapped around the spool determines how much thread is available for use. Adding or removing chemical tags affects how tightly DNA wraps around them. One of these common tags is an entails attaching an acetyl group to the histones, allowing more access to the DNA through a process termed histone acetylation. Although the study of other histone modifications associated with sleep is still in its infancy, the relationship between histone acetylation and sleep has been studied relatively extensively.

Histone acetylation is very crucial in gene expression. One of the main enzymes responsible for the action are called histone acetyltransferases (HATs), which as the name suggests, transfer acetyl groups to histones. On the other hand, the enzymes that remove the acetyl groups are histone deacetylases (HDACs).

One of these histone acetyltransferases (HAT) is a gene called CLOCK. You’ve probably heard about the circadian rhythm, which typically refers to the internal biological clock that controls our sleep cycle, and CLOCK is one of the specific genes that regulates this biological cycle. CLOCK performs this role by either increasing or decreasing expression of other genes involved in the circadian rhythm. Sleep deprivation leads to errors in the CLOCK activity, which can further disrupt sleep homeostasis and the circadian rhythm.

Another major way that sleep loss can cause problems is through the hippocampus. Recall that the hippocampus is responsible for learning and memory. The hippocampus is ultrasensitive to sleep deprivation, which can cause spatial memory loss. Specifically, lack of sleep lowers the levels of a specific histone acetyltransferase, called CBP HAT, and the messenger RNA (mRNA) that becomes translated to protein for this enzyme. At the same time, the level of histone deacetylases removing acetyl groups increases and the net result is an overall decrease in histone acetylation. This decline leads to lower expression of the genes crucial for maintaining hippocampal integrity, including a specific nerve growth factor called the brain-derived neurotrophic factor (BDNF). When there is a decrease in expression of this factor, it disrupts a series of signals in the brain that results in cognitive deficits and memory impairment. Research has shown this effect can be reversed Trichostatin A, which is an HDAC inhibitor that prevents the removal of the acetyl tags, illustrating the significant role that histone acetylation plays in memory and learning in the hippocampus.

Non-Coding RNAs

The last toggle switch controlled by your decisions about sleep is non-coding RNAs, which as the name suggests, do not become translated to proteins. Non-coding RNAs play many important functional and regulatory roles, so it is of no surprise that non-coding RNAs also play a significant role in how sleep can affect cognitive functions. In the context of sleep, the two types of non-coding RNAs of interest are long non-coding RNAs (lncRNAs) and microRNAs. As the prefixes suggest, the difference is in the length of the nucleotides that make up the RNA sequences. Long non-coding RNAs are on average 200 nucleotides long, while microRNAs are about 22 nucleotides long. Much like histones, lncRNAs are also closely linked to the circadian rhythm. Research has shown that removing lncRNAs in mice brains causes dysregulation of CLOCK and other circadian rhythm-related genes, and sleep deprivation has been correlated with differential expression of several lncRNAs in mice brains.

MicroRNAs are also able to regulate gene expression by binding to mRNAs. This binding results in subsequent degradation of the mRNA, thereby hindering gene expression. Many studies have shown that some microRNAs repress the expression of circadian rhythm genes, and the levels of these microRNAs have been shown to increase after sleep loss in rats. In the human brain, microRNAs are expressed differentially in specific brain regions depending on sleep periods, suggesting that sleep may regulate tissue-specific microRNA expression. Most importantly, microRNAs have been shown to play a direct role in inhibiting overall mRNA translation in the hippocampus.

Why do your brain and your body care?

Through a number of studies, it has become pretty clear that sleep deprivation has a significant impact on brain plasticity, as well as cognitive and metabolic function and may even play a role in some psychiatric diseases. In various mice studies on sleep wave patterns, DNA methylation has been found to have an impact on the genes and gene pathways involved in signaling, neurotransmission, and synaptic plasticity. Through electroencephalography (EEG), a technique used to record electrical activity in the brain, we also know that regulation of sleep activity is tied to synaptic downscaling, a method used by your brain to maintain plasticity and improve cognitive performance and learning.

Much research on histone modifications further links changes in the histone code from sleep disturbances to differential abilities in learning and memory, a and can link sleep disturbances to neurodegenerative and neuropsychiatric disorders. How healthy your brain is will also correlate with your mood, which may have a cyclic effect on how well an individual is able to handle specific psychiatric conditions. Finally, we know that lack of sleep can reduce your metabolic function, which leads to higher risk of obesity, as well as further complications such as heart disease, strokes, and abnormally high blood pressure.

There is still a lot of research to be done to determine how exactly sleep interacts with the brain and the implications of it, but this is certainly a start. From what we know, we have already started identifying how to combat sleep deprivation through stimulants such as caffeine and modafinil, which both help correct for the negative effects of sleep deprivation by targeting neurotransmitters in the brain such as dopamine and adenosine. However, we have only just begun to uncover the mechanisms involved, and further research could go a long way in helping identify how the link between sleep and epigenetics impacts the brain, the body, and the associated disorders and interventions that go along with them.

Now you fully understand what we mean when we say that your epigenome needs sleep, too. Sleep is an integral part of daily function and normal physiological processes because of how much of a role it plays in regulation and expression of genes involved in many important brain functions. Next time you have a lot on your plate, try to spread out your work so that you can get some sleep. Not only your body and grade, but also your epigenome will thank you. Get some sleep tonight!

References

Akers, K. G., Cherasse, Y., Fujita, Y., Srinivasan, S., Sakurai, T., Sakaguchi, M. (2018). Concise review: Regulatory influence of sleep and epigenetics on adult hippocampal neurogenesis and cognitive and emotional function. Stem Cells Journal , 36 (7), 969-976. https://doi.org/10.1002/stem.2815

Cedernaes, J., Osler, M. E., Voisin, S., Broman, J., Vogel, H., Dickson, S. L., Zierath, J. R., Schiöth, H. B., & Benedict, C. (2015). Acute sleep loss induces tissue-specific epigenetic and transcriptional alterations to circadian clock genes in men. The Journal of Clinical Endocrinology & Metabolism , 100 (9), E1255-E1261. https://doi.org/10.1210/JC.2015-2284

Davis, C. J., Bohnet, S. G., Meyerson, J. M., & Krueger, J. M. (2007). Sleep loss changes microRNA levels in the brain: A possible mechanism for state-dependent translational regulation. Neuroscience Letters , 422 (1), 68-73. http://doi.org/10.1016/j.neulet.2007.06.005

Gaine, M. E., Chatterjee, S., & Abel, T. (2018). Sleep deprivation and the epigenome. Frontiers in Neural Circuits , 12 , 14. https://doi.org/10.3389/fncir.2018.00014

Massart, R., Freyburger, M., Suderman, M. et al. (2014). The genome-wide landscape of DNA methylation and hydroxymethylation in response to sleep deprivation impacts on synaptic plasticity genes. Translational Psychiatry , 4 , e347. https://doi.org/10.1038/tp.2013.120

Nilsson, E. K., Boström, A. E., Mwinyl, J., & Schiöth, H. B. (2016). Epigenomics of total acute sleep deprivation in relation to genome-wide DNA methylation profiles and RNA expression. A Journal of Integrative Biology , 20 (6), 334-342. http://doi.org/10.1089/omi.2016.004

Tononi, G., & Cirelli, C. (2003). Sleep and synaptic homeostasis: A hypothesis. Brain Research Bulletin , 62 (2), 143-150. https://doi.org/10.1016/j.brainresbull.2003.09.004

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Aastha Dharia

Aastha is a senior majoring in Neuroscience through the College of Literature, Science and Arts at the University of Michigan, with a minor in Sociology of Health and Medicine. Her current research focuses on neuromuscular rehabilitation through brain stimulation and gait training. She is also heavily involved in developing student mental health initiatives on campus, building prostheses for children, and providing access to preventive healthcare in underserved communities. After graduating, she plans to spend a few years working in healthcare and eventually pursue a career in public health and medicine.

Danny Kim

Danny Kim is a junior with a major in Molecular, Cellular, and Developmental Biology (MCDB) and a minor in Gender and Health at the University of Michigan. Since his freshman year, he has been involved in research in head and neck squamous cell carcinoma at the Michigan Medicine Rogel Cancer Center. Outside of school, he is an active member in the acapella community, Central Student Government, and mental health awareness efforts on campus. He loves being outside, socializing with friends, singing his heart out, cooking, and drinking coffee. He intends to attend medical school after graduation and is in the process of applying in the 2020-2021 cycle.


Benefits and science behind emotional tears:

Crying is a necessary and an excellent way to release stress and purge our toxins out (through stress hormones present in our body).

Crying induces relaxation by activating our parasympathetic nervous system. It is the body’s way of relaxing you. So, if someone cries, it will help induce relaxation instead of increasing stress. The problems arise when we bottle up emotions within us, avoid crying, and let these emotions build up within us, leading to more hurt, sadness, anxiety, and a subsequent build-up of stress hormones. So, crying is not a negative response, but instead, a positive one.

Crying helps produce oxytocin and endogenous opioids (endorphins), which are feel-good hormones that can improve and elevate our mood, and even dull our pain. When we are hurt and have tears in our eyes in response to that pain, it is our body’s mechanism of handling the pain, improving our mood, and helping us feel better. So, let those tears roll down instead of holding them back and pretending to be strong.

Any emotional pain, be it hurt or betrayal is vital to be felt, instead of being numbed through means like shopping, partying, drugging, and so on. Crying helps us embrace the pain. Feel it, and let it die its natural death. It helps to train us on how to process these emotions. It also teaches us the grieving process, which is also a part of all tradition and religions when we lose a loved one. Our ancestors would take time to grieve for weeks and months altogether, but today we hardly grieve. We cry and feel sad, but move on with our life very early, and the process of grieving is left incomplete. An incomplete grieving process eventually results in these suppressed emotions cropping up later on in life, causing much more havoc. Emotions are energy in motion. They need to be processed. They cannot be contained, because we all know how suppressed emotions mostly manifest into possible diseases.

We cry when we are happy, content, and feel accomplished, and all of this can help bring balance in our emotions.

If there is something that is genuinely hurting you, cry it all out, and then try sleeping. You will find yourself sleeping with a lighter mind, and your quality of sleep will be much better. As discussed earlier, crying also puts us in a state of rest and digest, which is a favourable state to fall asleep in.

Crying teaches us to face our emotions head-on. Take your drugs, see a psychologist, take emotional support, and do all you want to, but when you feel like crying, cry it all out. This is your true solution, because only you can face the emotions that are bothering you. No one else will do it for you. Others can help, but eventually, you have to do it for yourself.

If you do not want others to see you crying, lock yourself in a room, and cry in privacy, or in front of a close friend, but understand that it is a mechanism built in us to help us survive and adapt ourselves in changing environments.

A hurtful event might have occurred a long time ago, but if it is still pulling you back, you need to process those emotions, face them head-on, and cry it out once and for all. It is okay to cry it all, out and feel every one of your emotions, rather than holding everything inside, and trying to put on a false façade which at some point, will get overbearing and confusing for yourself as well.

Only when you step back and study the amazing anatomy of your body and its intelligence, will you know that no single mechanism in our body is built without reason. So, let your tears flow, because holding onto them inside will only harm you more, and severely affect your emotional health and physical health as well.


Eyes send an unexpected signal to the brain

This subset of neurons is also involved in the synchronization of circadian rhythms to light/dark cycles and pupil constriction to bight light intensity.

Summary: A new study puts into question conventional belief that the eyes communicate with the brain exclusively via one signaling pathway. Researchers have identified a subset of retinal neurons that sends inhibitory signals to the brain. This subset of neurons is also involved in the synchronization of circadian rhythms to light/dark cycles and pupil constriction to bright light intensity.

Source: Northwestern University

The eyes have a surprise.

For decades, biology textbooks have stated that eyes communicate with the brain exclusively through one type of signaling pathway. But a new discovery shows that some retinal neurons take a road less traveled.

New research, led by Northwestern University, has found that a subset of retinal neurons sends inhibitory signals to the brain. Before, researchers believed the eye only sends excitatory signals. (Simply put: Excitatory signaling makes neurons to fire more inhibitory signaling makes neurons to fire less.)

The Northwestern researchers also found that this subset of retinal neurons is involved in subconscious behaviors, such as synchronization of circadian rhythms to light/dark cycles and pupil constriction to intense bright lights. By better understanding how these neurons function, researchers can explore new pathways by which light influences our behavior.

“These inhibitory signals prevent our circadian clock from resetting to dim light and prevent pupil constriction in low light, both of which are adaptive for proper vision and daily function,” said Northwestern’s Tiffany Schmidt, who led the research. “We think that our results provide a mechanism for understanding why our eye is so exquisitely sensitive to light, but our subconscious behaviors are comparatively insensitive to light.”

The research will be published in the May 1 issue of the journal Science.

Schmidt is an assistant professor of neurobiology at Northwestern’s Weinberg College of Arts and Sciences. Takuma Sonoda, a former Ph.D. student in the Northwestern University Interdepartmental Neuroscience program, is the paper’s first author.

Image from a mouse retinal section where cell nuclei are labeled in blue, RNA for the GABA synthesis enzyme Gad2 is labeled in magenta, and RNA for melanopsin is labeled in green. Image is credited to Northwestern University.

To conduct the study, Schmidt and her team blocked the retinal neurons responsible for inhibitory signaling in a mouse model. When this signal was blocked, dim light was more effective at shifting the mice’s circadian rhythms.

“This suggests that there is a signal from the eye that actively inhibits circadian rhythms realignment when environmental light changes, which was unexpected,” Schmidt said. “This makes some sense, however, because you do not want to adjust your body’s entire clock for minor perturbations in the environmental light/dark cycle, you only want this massive adjustment to take place if the change in lighting is robust.”

Schmidt’s team also found that, when the inhibitory signals from the eye were blocked, mice’s pupils were much more sensitive to light.


7 Ways To Reduce The Appearance Of Bloodshot Eyes

Waking up to red, puffy eyes can be a discouraging way to begin the day, and may leave you searching for ways to reduce the appearance of bloodshot eyes. And while there are plenty of over the counter eye drops and even whitening eye drops (don't go there, they actually aggravate the problem over time) on the market, you may be interested in some natural alternatives. Because whether or not you're a crunchy herbal enthusiast, treating red eyes with drops that may contain beta blockers or Chloramphenicol might seem a bit overzealous. Or, maybe you simply relish the idea of using what you have on hand in your garden and home.

Before we dive into aiding what ails us, let's take a few moments to further understand what causes red, bloodshot eyes. Unfortunately, the answer is: everything. OK, that's a slight exaggeration, but the eyes and their surrounding skin are extremely sensitive, and even common occurrences can take a toll on their appearance.

While there are a few more serious eye conditions, like conjunctivitis (pink eye), uveitis and glaucoma, and corneal ulcers, that result in redness (so, it is important to see an eye doctor if your redness persists or comes with impaired vision), many cases of red or bloodshot eyes are down to daily activity. Yes, staying up all night crying or smoking da herb will get you a solid case of red eye, but so will working at a computer for eight hours. In fact, digital eye strain has become a huge affliction, according to The Vision Council, which states that a whopping 70 percent of American adults experience digital eye strain or computer vision syndrome (myself likely included).

When it comes to other specific causes, essentially anything that creates dryness beyond what your tears can properly lubricate, like smoking (anything), hanging out in arid environments (whether they're a desert or a dry office), or becoming dehydrated, can lead to redness. Which, sadly, means that consuming a bunch of caffeine without adequate water will leave your eyes looking rosy, too. But dryness isn't the only culprit — putting pressure on your eyes or introducing them to irritants can also cause your eyelids to swell or the blood vessels on the surface of your eye to expand. That is to say, "Hello, seasonal allergies, meet my newly red and swollen peepers!" And simple things like sleeping face down, all snugly with your pillow, forgetting to remove your eye makeup or applying it carelessly, and swimming in chlorinated water without goggles can agitate your eyes. Even eating a lot of salty food can make a difference.

Luckily, with a little extra time and tenderness, most bloodshot eyes can be convinced to chill out. Employ these simple tips and remedies on days when your eyes need some love, and you're likely to feel both energized and uplifted. Taking the time for self-care is a vital, often lacking practice in our busy, work oriented society. So, when you spend a few moments to prepare homemade remedies and rest your body, you're not only receiving the benefit of reclaiming those beautiful, clear windows to your soul, you're also reminding yourself that you're valuable and worth treating with respect.

1. Spoon Those Eyes

Since reducing temperature has the effect of constricting blood vessels, which leads to decreased redness, swelling, and irritation, this simple method is a great option when you need to relax your eyes, but don't want to mess with much. Take four metal teaspoons and place them in ice water. Once they're cooled (not frozen), place two of the spoons, with the concave side toward your skin, following your eye socket's natural contour. Lay back, and relax. When the first set of spoons becomes warm from your body heat, replace it with the second set that's been chilling. Continue alternating spoons for up to 20 minutes.

2. Eye Rinse

Recommended by Stephanie Tourles, author of Organic Body Care Recipes, this soothing eye rinse works very well for tired, dry, and bloodshot eyes. Remember that with any home remedy, you want to ensure that your utensils and containers are sanitized before you begin.

Prep Time: approximately 45 minutes

Blending Tools: strainer shake before each use

Store In: sterilized plastic or glass bottle or spritzer

Yield: approximately 1 cup

Bring the water to a boil and remove it from heat. If you're using fennel seeds, crush them using a mortar and pestle. Add one of the herbs listed above to the boiled water, cover the pot, and let steep for 30 minutes. Strain the liquid twice through a nylon stocking, coffee filter, or very fine cloth.

Pour the strained liquid into a sterilized container. You can refrigerate this rinse for up to seven days.

Application: Splash the rinse into open eyes, or mist into open eyes. You may also use an eye cup, which I haven't been able to master, but don't let that stop you!

3. Tea Bags

The relaxing effect of reclining with cool, damp tea bags over your eyes is no secret. And while this trick has been around for quite some time, it's with good reason. Many green, black, and many herbal teas provide a variety of benefits, including the reduction of inflammation and redness. A few top contenders specifically worth applying to your eyes are green, black, catnip, rose petal, chamomile flowers, elder flowers, eyebright, fennel seeds, lavender buds, and blackberry leaves.

4. Remove Your Makeup And Lenses

Seriously, give those eyes a rest. Not only does leaving your makeup on cause premature aging for your skin, but doing so could also result in clogged tear ducts, which mean the potential for a stye, or simply not enough lubrication to keep your eyes clear and vibrant. Leaving your contact lenses in can be even more damaging, as they have a tendency to deposit microbes and other particulate on the surface of your eye. The last thing you want is to develop a fungal infection from leaving your lenses in too long.

5. Cool Eye Mask

Another gem from Organic Body Care Recipes by Stephanie Tourles, is this rejuvenating and hydrating eye mask. In fact, it's so lovely and refreshing, I'm going to mix one up as soon as I'm done sharing it with you!

  • 2 teaspoons cucumber or raw potato, peeled, seeded, and finely grated
  • 1 teaspoon powdered milk

Use: once or twice a week

Prep Time: approximately 35 minutes

Blending Tools: grater, mortar and pestle

Store In: do not store mix as needed

Using your mortar and pestle, combine ingredients into a smooth, thick paste and chill for 30 minutes. Add a few drops of water if mixture is too thick.

Application: Lie down, close your eyes, and finger paint your entire eye area, including your eyelids. Rest and relax for 10 minutes, then rinse your face with cool water.

6. Walk Away From the Screen

I know. It's hard. Not only because the Internet is an alluring, mind-boggling adventure land, but also because more than likely someone is paying you to stay shackled to your desktop or laptop. But if you get up and walk away from your screen, allowing your eyes to focus on things at varying distances and of various sizes, your eyes (and your body) will thank you.

7. Get Some Zzzzzs

Ah, my favorite way to reduce the appearance of bloodshot eyes! Let yourself luxuriate in a good nap, or a few hours extra every now and then. According to the Center for Disease Control and Prevention, many Americans are sleep deprived, and 35.3 percent of Americans are getting less than seven hours of sleep per day. Compromising your sleep means your heart is not working at optimum levels, nor are your thyroids or kidneys. These organs need adequate time to recharge, and skipping on sleep robs them of it. So, if you want to keep your eyes (and other organs) healthy, clear, and free of bags or dark circles, it's imperative that you hit the sheets.


How to Protect Your Eyes when Using a Computer

This article was medically reviewed by Theodore Leng, MD. Dr. Leng is a board certified Ophthalmologist and Vitreoretinal Surgeon and an Assistant Professor of Ophthalmology at Stanford University. He completed his MD and Vitreoretinal Surgical Fellowship at Stanford University in 2010. Dr. Leng is a Fellow of the American Academy of Ophthalmology and the American College of Surgeons. He is also a member of the Association for Research in Vision and Ophthalmology, the Retina Society, the Macula Society, the Vit-Buckle Society, as well as the American Society of Retina Specialists. He received the Honor Award by the American Society of Retina Specialists in 2019.

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Experts agree that spending time in front of a computer may cause eye strain. [1] X Trustworthy Source Mayo Clinic Educational website from one of the world's leading hospitals Go to source While eye strain typically isn't harmful, it can cause bothersome symptoms like dry, watery eyes, sensitivity to light, headache, and neck or shoulder pain. Fortunately, it's fairly easy to protect your eyes so computer use is less likely to bother them. Research suggests that making simple changes like re-positioning your screen, blinking, taking breaks, and adjusting your lighting may help prevent eyestrain. [2] X Trustworthy Source American Optometric Association Professional medical organization dedicated to supporting optometrists and improving public eye and vision health Go to source Additionally, you might incorporate other diet and lifestyle changes to protect your eyes.


Why You Should Stop Using Your Smartphone at Night

Here are 6 serious reasons why you need to stop using your smartphone at night:

1. It Can Damage Your Eyes

There is some evidence that blue light can damage our vision by harming the retina over time (1) and causing macular degeneration (the loss of central vision, or the inability to see what is right in front of you).

Artificial blue light is one of the shortest, highest-energy wavelengths in the visible light spectrum. Because they are shorter, the wavelengths flicker more easily, which creates a glare that can reduce visual contrast and affect sharpness and clarity (2). This is often the case for why people experience digital eyestrain and suffer from symptoms like blurry vision, difficulty focusing, dry and irritated eyes, headaches, neck and back pain, after a day’s work at the computer.

Since quitting using my phone at night, my mystery morning eye strain that would often last into the afternoon went away. It felt like I hadn’t slept at all, but really, it was just the effects that the blue light had on my eyes.

2. Sleep Loss

Blue light disrupts melatonin production, which directly translates to sleep loss. Melatonin is the hormone that regulates the body’s sleeping cycle. If your sleep cycle isn’t properly regulated, you won’t be getting the amount of sleep you truly need. Sleep loss results in a variety of different health problems, such as those mentioned here.

3. Higher Risk of Cancer

Melatonin is one of the most important antioxidants that our body produces naturally. Since melatonin is suppressed by blue light emitted from smartphones and tablets, then your body is essentially being depleted from this powerful antioxidant. Disrupting melatonin production for one night wouldn’t be a serious issue, however, some people are on their phone chronically from night to night for hours at a time.

Lack of sleep can raise your risk of breast, colorectal and prostate cancer, to be specific (3). Lack of melatonin means a higher risk of cellular damage, higher inflammation rates and disruption of normal immune function (all 3 major roles that melatonin is involved in preventing).

4. Depression

People whose melatonin levels are suppressed, and whose body clocks are modified by light exposure are also more prone to depression. Lack of sleep interferes with our neurotransmitters, and can ultimately lead to a decline in synaptic signaling between neurons, which normally regulate our mood (4).

5. Weight Gain

By disrupting our melatonin production and sleep cycles, smartphone light emissions at night can also mess with the hormones that control hunger, increasing the risk of obesity. According to Dr. Siegel, lack of sleep can ruin your insulin levels, which directly affects your body’s metabolism (5). If your metabolism is messed up, then your weight will be, too.

Getting less than seven hours of sleep at night can also prevent our glial cells from cleaning up the toxins that our brain cells produce. In over 95% of people, these toxins remain in the body and not surprisingly, contribute to weight gain.

6. Disrupts The Brain

Not getting enough sleep caused by smartphone light can also make it harder to learn, and may leave you distracted and impair your memory the next day (6). When comparing the brain of sleep-deprived individuals with those who have received plenty of sleep, scientists have found reduced metabolism and blood flow in multiple brain regions. This results in impaired cognitive function and behavior.


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