Visual Stress, Light and Migraine

By 9 March 2021June 1st, 2022Health, Latest

Visual Stress, Light and Migraine


Photophobia is translated as the ‘fear of light’ however it’s more of an intolerance or sensitivity to light than an actual fear. It can be called Photosensitivity, but this also includes a skin sensitivity so may not explain it adequately, so we’re back to photophobia!

Light can be particularly bad at this time of year when the sun is slowly climbing its way back up the firmament into its favourite spot for summer. Many people find light on its own bad enough, but others are more affected by patterns of light such as dappled sunlight or the sun flashing through railings, or the streetlights outside their house, LED lights on cars, etc. Everyone’s sensitivity or tolerance for light and patterns is different.

A few years ago, Dr. Paddy Daly, then head of the Migraine Clinic in St. Vincent’s Hospital and one of MAI’s medical advisors, since retired, wrote an article for us on visual stress. He pointed out how people with migraine are susceptible not just to bright light, noise and smell but to patterns, bright colours and flickering from TV and computer screens. These may not be things that our eyes see, but they are things that our brains pick up. Visual stress is more related to the brain than it is to vision, our eyes are simply the receptacles that capture the information which is then relayed to our brains.

Many things can cause visual stress to us.
  • Flicker on TV/computer screens
  • Dappled sunlight through trees or railings
  • Bright glare on walls or white boards in classrooms and offices
  • Fluorescent lights
  • Bright LEDs and other lights
  • Patterns in furniture, carpets and on walls

Here’s Dr. Daly’s Article to explain visual stress…

People who suffer migraine are very aware that as the migraine develops, sensitivities to light, sound and odours are common experiences. In particular light sensitivity might be a constant presence between attacks.

Visual Cortical Stress is a term put on the hyper-excitability that exists in the visual cortex of the brain even between attacks of migraine. Glare can be very uncomfortable for those with migraine and wearing sunglasses can be beneficial. Look for polarized sunglasses which reduce glare much more than plain darkened glass; however they are not easily used indoors.


Not so well known to people is the stress caused by patterns. They may be in the form of stripes or gratings, but also include patterns of noise at a particular pitch or resonance. Certain frequencies cause trouble and this is an individual response so people will be aware of what will be an issue for them personally. Some examples might be open-plan office noise, or factory floor noises, especially if high pitched.

Imperceptible flicker from fluorescent and TV screens may increase the hyper excitability in the brain leading to migraine. Patterns also exist in reading with striping effects in some words such as ‘will’. Where such words come together visual stress increases. A relatively new form of pattern stress exists in headlamps of cars using LED lights. Not only are they bright but many have irregular patterns. Night-time driving can become very stressful.

The problem with patterns extends beyond lighting to involve the surrounding environment and can include decoration such as striped carpets or designs on walls. (At a conference Dr. Daly used the example of a patient of his who worked in a hotel. She suffered from migraine attacks badly on the days she was on reception, but if she was elsewhere in the hotel, she was generally okay. Only after a lot of exploration, she realised that the new carpet that was put into the hotel lobby had a very busy, dizzying pattern and when she worked in reception, she crossed the carpet several times a day. Her brain was picking up a pattern she had barely noticed.)

What can you do?

There is accumulating evidence for the use of coloured filters to reduce visual stress. For reasons that are not understood, colour needed varies from person to person. Theses tinted lenses are eminently usable indoors as opposed to sunglasses because they do not dull the light, they just dull the frequency to which the person is sensitive. The test is called an ‘Intuitive Colorimeter Test’….”

Other Visual Stress Factors

Another factor may be a disorder called Irlen Syndrome. Again, this is a perception issue rather than a visual one. It is a disorder of the way our brain interprets light signals and can interfere with reading and how we see the text of the page before us. Many of the symptoms of Irlen syndrome are similar to those of migraine, such as light sensitivity, nausea, tiredness, headache, sore or watery eyes, with distortions in print like wavy lines, ghosting or seeing patterns in word such as ‘will’ and in the layout of the text on a page where you might see what are called ‘rivers’ running through the page. See the following link for examples of these disturbances but be aware they may trigger an attack so proceed with caution…

Irlen Syndrome

Those who suffer from Irlen syndrome often find that using a coloured filter on their phones, books, or wearing glasses with a coloured lens help a lot. These glasses are not like reading glasses, instead the colour filter seems to relax the brain and allow for the correct interpretation of the light signals so that we can read and study, etc in comfort without bringing on headache, migraine or any other problems. or are two great websites which allow you to change the colour of the text areas to see if any particular colour makes it easier to read the information. I find bright white on a screen sometimes difficult to watch so I tried it. On both websites, I found that the dusky blue or purple colours made a big difference to me. I felt my eyes relax straight away and it was much easier to see everything. As a result, I changed the page colour I used on Microsoft Word while typing out this post and it really helped.

People with dyslexia sometimes use coloured lenses. The Dyslexia Association of Ireland also has coloured filters on their website.

What about Blue Light? Can it Trigger Migraine?

First, what is blue light and why does it affect us so much? Okay, here’s the science part… Very simply put, Blue Light is one of the colours that we can see in what’s called the Electromagnetic Spectrum. This includes all light both invisible (Ultraviolet or UV light) and the colours we see in things like rainbows, clouds, certain glass when light shines through, etc. Light travels in waves and these waves have different lengths. The shorter the length, the more energy it emits, and blue light has a shorter wavelength than other colours, which means it has higher energy. So there you go…

Blue Light

Natural blue light is actually good for you. The sun is the biggest producer of natural blue light and it does everything from making the sky blue, boosting our mood and happiness, to keeping our circadian rhythm in sync. The problem with artificial blue light is that while using our devices, screens, LED lights etc., we’re getting too intense a burst from both the proximity of the screens and the length of time we’re exposed. Blue light flickers more than other types of colours in the spectrum. Our eyes can filter out certain things, like UV light, but blue light is too strong and too unsteady, and if we’re staring at it for 8 hours or more at a time, we’re not doing ourselves any favours. It can trigger migraine.

Aside from the sun, these are the most common sources of blue light;

Here’s an interesting piece by Theraspecs on how blue light affects us and a couple of things you can do to help yourself, including…

‘How Can You Reduce Blue Light Exposure?

The last thing you want to do is shut yourself in the dark because that can have physical and emotional consequences, so what are your options? Here are some ways that you can minimize the damaging effects of blue light:

  • Try “blue blocker” or blue-light filtering glasses
  • Use “night mode” or similar apps that are native settings on your phone and your computer. This can warm the lighting on your device and make it easier on the eyes.
  • Turn your phone or computer off at least 2-3 hours before you go to bed.
  • Change your light bulbs to warmer tones and colors. Opt for more natural light if possible and avoid/remove fluorescents, if appropriate.
  • Give your eyes a break. Look away from your screen at least once every 20 minutes to let your eyes reset. And don’t forget to blink!’
Further Information

Our former Communications Officer Debbie Hutchinson produced a very helpful piece about migraine and light at work which is in this PDF MAI Migraine and Lighting in the Workplace.

Here are some links with information on light, visual stress and migraine and for eye-wear and a few opticians who may be able to help. If you know of other opticians or optometrists who might be able to help, or if you are an optician or optometrist with an interest in visual stress, then please contact us on if you’re happy to help migraine sufferers.

  1. Teahan’s Specialised Services, Naas –
  2. Aisling O’Connor Visual Stress Specialist Opticians – Cork –
  3. Elliot’s Opticians – Athlone
 Specialist Eye-wear:
  1. Galway:
  2. Kildare/Cork/Mayo:
  3. Ireland: – Newly established Irish Company
  4. Irlen Syndrome –  and
  5. Axon Optics and TheraSpecs in the US do post their migraine glasses to Ireland. – Theraspecs has a fairly good newsletter you can sign up to and here’s an interesting PDF Theraspecs LightAndYourHealth
Screens and filters:
  1. F.lux – Filter you can time to copy natural daylight on computer screens, tablets and phones
  2. Ocushield – Screen guards for phones, monitors, tablets and do blue-light-blocking glasses
  3. IrisTech – Filter blocking blue light
  4. ‘Twilight’ and ‘Blue Light Filter’ are two apps that can be downloaded for phones and tablets. There is a blue light filter already on iPhones from iPhone 5 and iPad 2 onwards

The information contained in this article is for information only and not intended to replace medical advice or diagnosis.