What is Irlen® Syndrome?


Irlen Syndrome® (Meares-Irlen Syndrome, Scotopic Sensitivity Syndrome, or Visual Stress) is a perceptual processing disorder rather than an optical problem. The brain has difficulty in processing visual information. The problem can run in families and is not currently identified by other standardised educational or medical tests.

How can it affect me?

There are a variety of different symptoms that affect adults and children, the most common symptoms include:

Light Sensitivity

You may be bothered by glare, fluorescent light, bright light, sunlight and sometimes lights at night.

Reading Problems and/or text distortion

You may have difficulties with learning to read and/or comprehension. Words on a page may lack clarity or stability, appear blurry, move or may even disappear.

Attention Problems

People can sometimes appear to have other conditions, such as ADD when in fact, they have Irlen Syndrome.

Strain and Fatigue

You may be frequently tired or sleepy.


You may experience headaches or nausea, particularly when reading.

Depth Perception

You may experience such difficulties as clumsiness, difficulty catching a ball or cannot judge distance. Adults may be cautious when driving.