How your eyes can give you a headache

Our perception of the world relies on a complex interaction between our brain and our sensory organs. Sensory stimuli that we receive through our eyes, ears, nose, mouth, and skin are converted into signals and processed by the nervous system to allow our brain to create a picture of our surroundings.

When we see, our eyes constantly send feedback to the brain about the visual stimuli in the world around us. Every second we are awake, signals are sent to the brain that shape our impressions of the world. Through complex calculations, the brain turns information it gets from our eyes into what we recognize as our image of reality. We’re usually unaware of this process – indicating that our eyes and brain are working together smoothly. But if something goes wrong anywhere in the process, the results may manifest themselves in symptoms like headaches.

When focusing doesn’t work

For the eye to produce a sharp image, a complex process is needed, one that we’re usually unaware of. This process is called “accommodation”, which essentially means “adjustment” in this context. The lenses of our eyes are flexible and attached to tiny muscles that can change the shape of the lenses through contraction or relaxation. This allows our retina to capture a clear image of objects, whether near or far. Our eyes receive the commands to focus from the brain, which processes images as they come in and “orders” corrections if needed.

For various reasons, this accommodation process may be disrupted. The muscles involved may need a couple of attempts to capture a clear picture. In other cases, there may be excessive tension in the muscles, resulting in “over-accommodation” and even causing spasms in the fine muscles. This can make it very difficult to see objects clearly. Rapid shifts between near and distant views may be impossible or take much longer than usual. The overwhelming strain on both the brain and the eye muscles may lead to eye pain and headaches.

Blurred vision and being unable to see what’s going on around you can be very unsettling and stressful. To compensate for any visual impairment as effectively as possible, glasses need to be tailored precisely to correct the individual vision issues. “Accommodation exercises” also come highly recommended. These are designed to train both eyes to work together and strengthen your focusing muscles to create a sharper image more quickly and effectively. This can also help stop your eyesight from deteriorating further.

Overworked eyes

When nearsightedness or farsightedness goes undiagnosed, the eyes are constantly exposed to excessive strain. In many cases, headaches are the inevitable result. Similarly, if eyesight deteriorates gradually even with corrective lenses, headaches may arise. This is why you should get your eyes checked regularly by a doctor.

Even perfectly functioning eyes can become overwhelmed. Reading or close work that requires constant refocusing for long stretches puts pressure on the optic nerve. Poor lighting – or overly bright lighting – also contributes to causing headaches.

Convergence excess

Convergence excess is an eye condition where the eyes do not work together properly. When focusing too intently on a close object with both eyes, individuals tend to move it closer and closer to their face, causing their eyes to turn inward in a sort of squint.

Symptoms of convergence excess mainly occur during extended focus. Typical scenarios would include prolonged reading or computer work – everyday life for university students. The associated intense strain on the eye-brain system frequently leads to headaches. To make matters worse, intense concentration can mean you don’t notice prolonged periods of poor posture with your head, neck and shoulders misaligned. Spending long periods in awkward positions strains the muscles, which in turn can trigger headaches.

Dry eyes and headaches

Keen readers are also familiar with dry eye syndrome (DES), also known by the somewhat unwieldy term “keratoconjunctivitis sicca” (KCS for short, from the Latin siccus, ‘dry’). Dry eye syndrome happens when you don’t have enough tears to lubricate your eyes. Symptoms include dryness, burning, itching, eye pain and vision problems. Dry eyes can also lead to headaches, nausea and dizziness.

Conversely, headache disorders are a significant cause of issues with dry eyes, as shown in a large meta-analysis involving comparative evaluation of 11 research studies. The researchers looked at the proportion of patients with migraines, tension-type headaches and cluster headaches who also had dry eye. The risk of dry eye syndrome was highest among those with migraines, followed by people with cluster headaches. However, people with tension headaches were also diagnosed with DES at higher than average rates.

When “snow” obscures vision

Visual snow syndrome (VSS) is a vision disorder often reported in people who also suffer from migraines. People with VSS report a kind of “static” (“visual snow”), like small particles, fluff or specks moving like snowflakes across their field of vision. Because VSS occurs so often in combination with a migraine attack, it was previously thought to be part of migraine aura. More recent research provides different insights. True, VSS and migraine aura share a number of traits, such as excessive excitability of the nerve cells in the cerebral cortex, which may indicate similar pathophysiological causes. Nevertheless, VSS is classified as a neurological condition in its own right, with symptoms that can go beyond those of a migraine aura.

Some people with the condition have trouble with night vision. Some may see double or “afterimages” of objects no longer in their field of vision. These visual disturbances often cause dizziness and headaches, as the brain strains to make sense of the mixed signals, bringing its resources to the brink of exhaustion.

Research into treatment options for this debilitating condition is still in its early stages. Encouraging prospects come from recent, non-medication-based treatment approaches in the field of mindfulness-based cognitive therapy (MBCT). This relatively new method combines elements of mindfulness-based stress reduction with cognitive behavioral therapy, which has long been successfully used in the prevention and treatment of headache disorders. However, research in this area is still in its early stages, and most affected individuals have yet to receive effective treatment.

Where does it hurt?

Distinguishing between eye and headache pain can be challenging. For instance, headaches felt “behind the eye” may actually be eye pain. Eyes can be painful for many reasons. Tiny corneal injuries can be excruciating, and allergies often cause eye pain in addition to itching and redness. Other possible causes include inflammatory conditions affecting the iris, eyelids or sclera (the white part of the eye).

The close proximity of the eyes and the brain coupled with the intense interaction between our organs of vision and the central nervous system may lower the pain threshold, ultimately leading to headaches. In this process, the body’s pain-enhancing signaling pathways become more active, while its pain-blocking signals weaken.

What can be done?

Anyone with vision impairment should see an eye doctor for regular eye health checks and adjust their corrective lenses as needed to respond to changes promptly and help prevent any deterioration. Those experiencing eye discomfort without a known cause should see a specialist to obtain an accurate diagnosis.

To prevent daily eye strain – whether or not you have a vision impairment – it’s helpful to rest your eyes on a regular basis. Especially if reading or screen work requires close focus, take regular breaks and look at something else to offset the effects. Gazing into the distance – such as looking out the window – eases the strain on your optic nerves and stimulates other regions of the fine eye muscles. Closing your eyes for a few moments while slowly breathing in and out can also be very relaxing.

It’s also important to set up your workplace in a way that’s as comfortable as possible for your eyes. Working at a comfortable distance is important for screen tasks, whether you’re working from a desk or on the move with your laptop, and it’s important to avoid leaning too close to the text when reading a book or any other device. Proper lighting is also crucial. Daylight may seem more comfortable than artificial light. However, depending on the weather, natural lighting conditions can change quickly, which can actually put a lot of strain on the eyes. Lighting in general should not be dim, in order to ensure that content is easy to see. On the other hand, overly bright lighting can be challenging, especially for people with migraines, as some may be particularly sensitive to the flickering of fluorescent lights.

Identifying specific factors that trigger discomfort can help in making adjustments to your daily routine. Taking regular breaks is essential, and those who need a reminder can use the Headache Hurts app to prompt short, frequent breaks. Interrupting work to change your posture, giving your eyes a chance to rest, and relieving tension in the shoulders, neck, and the rest of the body can help prevent headaches. When we are deeply focused, we often don’t realize how long we’ve been staring in one place. Regular stretching and gentle movement helps ease tense muscles.

Intentional, longer relaxation periods with closed eyes also support recovery for both the eyes and the head. Progressive muscle relaxation has proven particularly effective in practice. You can find a short version of this useful relaxation technique on the website and in the app that’s easy to integrate into your life. Regular exercise, ideally outdoors, relaxes the nervous system and provides contrast for eyes exposed to close-up work. Gradually integrating these practices into your routine can do wonders for both your eyes and your head.