About Visual Stress

Visual stress is a neurological condition. It is a problem with the brain's ability to process visual information such as patterns, light and movement. These images cause the brain to become overexcited and not function properly, leading to physical discomfort and perceptual processing difficulties. It can interfere with reading, attention, coordination, general health and behaviour.


Commonly reported symptoms of visual stress include headaches, light sensitivity and fatigue as well as reading and attention difficulties, dizziness and nausea. Visual Stress is not a problem of the eyes and is not identified in standard optometric testing.


Symptoms are often alleviated with individually selected precision tinted filters. Without the appropriate filters, people often experience: 

Pain – Lights and patterns can be painful, and comfort is often found in the dark. 


Distraction – Glare, flashing or movement can be distracting and make it difficult to focus.  


Exhaustion – Distortions and discomfort can lead to physical fatigue, cognitive fatigue, and brain fog.   


Frustration – Knowing what you were like prior to your concussion, or watching classmates read without struggling can be frustrating. Closing your eyes is not a solution when you need to study, work or just get through your day. Nothing else you have tried seems to help.  It may be visual stress!

Learn about how to reduce your visual stress and what causes it:

Causes and Triggers

Understand how it happens and what triggers need to be changed to stop it

Signs and Symptoms

Recognize the indicators so they can be addressed and managed 

Related Conditions

Learn what other neurological conditions share symptoms that might be helped

Visual Stress


Find out about the scientific research behind visual stress and over 30 years of research 

Understanding the Visual Stress Process


For visual stress to occur, the visual system goes through several steps.  Understanding these steps can help you to stop the process by reducing the triggers and making changes to your visual environment.  If you do not make changes and the cycle continues to escalate, the stress accumulates, and symptoms will worsen. 

The process begins when an individual looks at a trigger image. Trigger images have a strong pattern, are high in contrast, flicker, move or are an uncomfortable colour. 

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The image information is sent to the visual cortex where it is supposed to be converted into a clear image that the rest of the brain can now use to make decisions and carry out tasks.

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If the visual cortex is sensitive to this information, an internal alarm goes off in the brain, activating the area and calling for oxygenated blood (energy) to manage the issue.

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If it continues to be activated, then an excess amount of energy is sent to the area.  This is called hyperactivation and means that the visual system is now under stress, and the individual is now experiencing visual stress.

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6) Vestibular issues: 

Perception of the visual environment may be misperceived as uneven and unstable causing dizziness and nausea from movement.  

5) Visual Illusions 

Perception becomes a problem, Text images may appear unstable, causing tracking and reading difficulties, light and glare may appear overly bright.  

4) Fatigue and frustration: 

Cognitive energy is running low and continues to be spent to process the image. Fatigue and frustration is often experienced. 

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1) Pain, pressure and heat:

The visual cortex fills with this oxygenated blood (energy). Pressure, pain, and heat at the back of the head (where the visual cortex is) is often reported 

2) Slower processing: 

As the energy collects the pathways become clogged, processing slows, and symptoms of brain fog and difficulty concentrating are often reported. 

3) Loss of Clarity: 

Information is no longer processed properly, and visual information loses clarity. Intermittent blurring may occur, leading to squinting, eyestrain and visual discomfort. 

Note: If the trigger image continues to be received by the brain the process flow continues around and around, and the visual stress symptoms increase in number and severity. As the excess oxygenated blood accumulates, it cascades into other areas of the brain, causing more, seemingly unrelated problems such as auditory sensory overload and migraines. The best way to end this vicious circle is to stop what you are doing and looking at. Alternatively, you can look into precision tinted lenses and other products offered by Opticalm. 

It is essential to see an optometrist for a full assessment and to have any anomalies treated conventionally before considering treatment with coloured filters.  

Opticalm requires all clients who come in for a Visual Stress Assessment to have undergone a detailed optometric evaluation within the past year and to be wearing comfortably, their new vision prescription.

If you are not wearing the correct prescription in your glasses (uncorrected refractive error), you might experience symptoms similar to visual stress. If your eyes have problems aligning visual images (binocular instability), you may also experience visual stress-like symptoms. The perceptual illusions caused by visual stress may increase difficulties with accommodation and vergence. These difficulties can sometimes be reduced when coloured filters are used.


The need to provide a low plus (hyperopic) prescription to relax the eyes may not be necessary when the visual system is calmed with precision coloured filters. 

Investigating for visual stress is not part of a routine optometric examination. Therefore, if symptoms persist after conventional vision care, it is advised to get an assessment for visual stress.  

Contact us for more information.

See an Optometrist