Without a regulated visual system, we cannot focus on the important details that help us understand the world around us. We are constantly surrounded by a range of objects and resources but, with a regulated visual system, we can focus on the details we need to and ignore those we don’t. Some children are unable to filter out the unwanted visual stimuli. The wealth of objects they see may be a constant distraction and can overwhelm them, resulting in them not being able to focus and engage. These children may have difficulty selecting the appropriate

visual information: this will make it difficult for them to respond appropriately in given situations. Their responses can appear as unwanted behaviour. 

For more information about vision see the Vision and Hearing section- visual processing, visual sensitivity, visual stress and the impact of visual impairment on social interaction.

Visual Processing

What is Visual Processing?

Visual Processing is the way the brain makes sense of visual information. It includes how the eyes work together (binocular vision), tracking of the eyes whilst reading, making fast eye movements, visual comfort and the perceptual aspects of vision. When a child or an adult has difficulties with visual processing this can produce signs and symptoms and they may be referred to an orthoptist who specialises in this area.

Some people with Autistic Spectrum Disorders and other developmental conditions suffer with a visual- perceptual problem caused by hypersensitivity to colour, lights, glare, patterns, and contrast. At its most severe, vision may be so problematic that a child may literally have a visual whiteout and temporarily lose the ability to see.

Signs and symptoms of visual processing difficulties

Signs that your child may be having difficulties with visual processing include:

Under Responsive:

• Difficulty finding equipment in visually busy backgrounds.
• Struggles to locate friends in the playground.
• Struggles to find where they are on the page.

Over Responsive:

• Doesn’t like bright lights.
• Prefers darker rooms.
• Covers or shades eyes.
• Excessive blinking, eye watering when there is a change in ambient lighting conditions.
• Wears peaked cap, keeps hood up indoors or insists on keeping their hair long over their face.

Seeker:

• Looking at shiny objects.
• Flickering fingers.
• Enjoys flashing lights and colours.

Visual processing difficulties that affect reading can be identified in a child (over 7 years) or adult who either does not require glasses and has some or all of the following difficulties or still has these difficulties below despite wearing their glasses.

Following reading do you or your child notice any of the following?

• Frowning, scowling or screwing eyes up with visual tasks
• Blurry vision at any time
• Print jumbling or merging together
• Seeing double
• Holding books too closely or too far away.
• Tilting of the head
• Poor posture/ wriggling at desk
• Moving head excessively or forwards or backwards while looking at the page
• Red eyes or lids
• Pain around the eyes
• Headaches, especially around the front of the head
• Excessive eye watering
• Rubbing eyes frequently
• Closing or covering one or both eyes in bright light or during visual tasks
• Repeatedly confusing right / left directions
• Skipping or re-reading words or letters
• Reversals when reading e.g. was/saw, on/no, b/d, p,q
• Transposing letters when writing
• Losing place frequently when reading
• Uses finger as a marker when reading
• Repeatedly missing ‘small’ words
• Getting confused by symbols such as + /-
• Mistaking words with the same or similar beginnings or endings
• Failing to recognise the same word in the next sentence
• Confusing the same word in the same sentence
• Struggling to remember sequences
• Struggling to copy from the board

If there are a few sections that you or your child have difficulties with and the child is over the age of approximately 7 years (as some of these difficulties are normal for younger children) then we would suggest an Orthoptic assessment. It is important that an Orthoptist be involved in the assessment of these difficulties as we are specialists in assessing binocular vision and eye movements.

Orthoptists will:

• Determine visual problems relating to reading and writing skills
• Manage the visual processing difficulties in a child or young person centred way
• Offer support to parents and teachers
• Offer advice and guidance to schools, Colleges and Universities

https://www.orthoptics.org.uk/patients-and-public/visual-processing-difficulties/

Ask your GP or optometrist to make a referral to Royal Cornwall Hospital Trust.

Strategies that might help

• A child with difficulties processing visual stimuli may benefit from a designated area to complete work in order to focus their attention, if necessary.
• If a child becomes disturbed/ distracted if there is a lot of movement around them then limiting distractions will enable the child to complete tasks.
• The child may benefit from engaging in tactile, proprioceptive and vestibular activities incorporating visual challenges such as using targets and completing sequencing tasks.

Vision involves more than the eye’s ability to detect images in the environment correctly, your brain must also process what the visual information means, remember it, be able to follow it as it moves or you move, know whether you need to respond to it, and if so, determine the best way to respond.

Stimulation of sensory receptors in the eyes generates an impulse to the optic nerve, which sends the sensory messages to various sites in the brain where the information is perceived, sorted out, and linked up with

NHS Orthoptic Visual Processing Difficulties (VPD) Clinic

An Orthoptic Visual Processing Difficulties (VPD) Clinic is a clinic run by Orthoptists to help children with eye problems related to or contributing to a reading or specific learning difficulty.  Speak to your GP or optometrist for a referral to the Royal Cornwall Hospital Trust (RCHT).

Visual Sensitivity

Does your child complain that the lights are too bright — or want to wear sunglasses all the time? Some children are very sensitive to the input that comes in from their visual sense.

The first step would be to have an eye test to rule out any eye health problems or needing glasses. 

Possible types of Sensitivity

Light sensitivity- Bright lights, sunlight, glare, and fluorescent lighting bombards the nervous system and can result in fatigue, anxiety, dizziness headaches, and other physical problems. Problems with light flickering can range from excessive eyestrain to seeing a room pulsate on and off. Fluorescent lighting can be a problem in that reflections bounce off everything in a room and can be blinding.

Contrast sensitivity- For some children when reading, the white background competes with the black letters, making letters lose their distinct edges.

Impaired print resolution- Letters appear to be unstable, and shimmer, move, shift, or break apart.

Distortions in the environment- For some people, objects disappear and lose their meaning, for example in a quick moving environment i.e. a busy hall, perceptually the hall may not exist, seeing instead only shapes and colours moving around. The visual system can become completely overloaded with stimuli and all meaning in visual sensation can be lost. A child may therefore resist climbing stairs, avoid eye contact, and prefer to remain relatively still.

Visual skills are closely linked with motor skills. We use our eyes to guide our hands and feet for any new skills. As a child learns to use the computer keyboard for example, they will look at their fingers. As new movement patterns become familiar, as mental maps for doing things get ingrained, your child relies less and less on vision. They will then be able to look at the computer screen as they type. That’s a result of the proprioceptive and vestibular systems taking over.

These issues can make everything from studying to falling asleep a challenge. Here are some ways to help children who have visual sensitivity.

1. Modify lighting.

For children who find bright lights overwhelming, dimmer lighting can be soothing. Consider using coloured light bulbs or compact fluorescent lamps — the light is softer. You can also invest in a flexible multi-head floor lamp. You or your child can adjust the positions of the bulbs for comfort.

2. Reduce glare.

If your child is oversensitive to sunlight, there are a few things you can do to limit exposure. Get sunglasses to keep in the car or in your child’s backpack. Talk with teachers about moving your child’s desk away from direct sunlight. You can also invest in portable shades that can be suction cupped to car or classroom windows.

3. Make things brighter.

Some children are under sensitive and need more visual input. Try using colour systems to help organize belongings so it’s easier to find them. Provide bright lighting for your child’s room and homework space. You may also want to consider investing in a projection night-light or lamp to help your younger child sleep.

4. Tone things down.

Bright colours and “visual clutter” can overwhelm some children. It can make it hard for them to concentrate or even become calm enough to sleep. Help keep your child’s room neat and keep distracting posters and knickknacks to a minimum.

5. Ease up on eye contact.

Some children with sensory processing difficulties find it hard or distracting to make eye contact. Telling kids to look at you might make it hard for them to concentrate on what you’re saying. Instead, let them know they don’t need to look directly at you, but they do need to listen and show that they’ve heard you. If seeing what you’re doing is important, ask your child to look in your direction.

6. Address safety concerns.

Some children have trouble visualising where their body is in relation to other objects. They may even tend to bump into things or trip over them. If your child has these difficulties, you might want to think about how you decorate your home.  Busy patterns on wallpaper or rugs can make it hard to see where things begin and end. Decorating in simple, contrasting colours can help. You can also use coloured tape to highlight doorframes and other potential trouble spots.

https://www.understood.org/en/articles/6-ways-to-help-your-child-cope-with-visual-sensitivity

Visual Stress

The term “Visual Stress” is sometimes used to refer to the collection of symptoms and signs of visual fatigue when reading that are reduced when colour is used as therapy. Other terms are Meares-Irlen syndrome, Irlen syndrome or Scotopic Sensitivity Syndrome (SSS). (The syndrome is not yet widely recognised by the medical and scientific communities, and there is no universal agreement on its name.)

Coloured overlays reduce the perceptual distortions of text that children sometimes describe. They enable some children to read text more fluently and with less discomfort and fewer headaches. Each individual seems to need a different colour, so it is important to assess the effects of a wide range of colours.

In several studies, children in county primary schools were individually shown a passage of text covered in turn by a variety of coloured overlays, including grey or clear overlays for comparison. About 20% of the children found one or other of the colours improved the clarity of the text. They continued to use an overlay of that colour without prompting for more than three months. They read more quickly with their overlay, both before and after they had become accustomed to its use.

What are the symptoms of Visual Stress?

• glare from the page
• headaches when reading
• sore eyes when reading
• movement/blurring of print

What are the signs of Visual Stress?

• rubbing eyes
• excessive blinking
• poor concentration
• inefficient reading
• difficulty in keeping place

Which children benefit?

The children who benefit may be good readers who tire quickly, but more often they have difficulty reading. They usually suffer visual discomfort when reading and, when questioned, will often report perceptual distortions of the text. These distortions usually include apparent movement or blurring of the letters and words. Often there is a family history of migraine.

Does visual perceptual distortion relate directly to learning difficulties, or dyslexia?

Children with reading difficulty are more likely than others to report visual perceptual distortion, and to benefit from coloured overlays. A smaller proportion of good readers also show similar benefits. Individuals with dyslexia may have difficulties with visual perception, but usually also have difficulties of a linguistic nature which need to be addressed separately.

Do children need coloured overlays or coloured glasses permanently?

It seems that children benefit most from colour if it is offered as soon as any reading difficulty is suspected, before the cycle of failure has begun. Many 7-year-olds appear to use coloured overlays for a year or two and then discard them as unnecessary. This may be because the acquired familiarity with text then makes the distortions less distracting.

Should children with binocular difficulties who are undergoing orthoptic eye exercises or other medical treatment continue to use overlays?

In our opinion, overlays can be used regardless of any simultaneous eye exercises or medical treatment. However, since visual perceptual distortions can sometimes be caused solely by binocular vision problems, it is often sensible to have these corrected first. If the distortions remain then coloured filters need to be tried.

Coloured glasses have been shown to reduce headaches in open trials and also in two small-scale trials using a double-masked protocol. The colour optimal for overlays differs from that optimal in lenses. Imaging studies of patients with migraine have shown that it is only when the shade is precise that a reduction in an otherwise abnormally large blood oxygenation occurs. Given the general association between elevated blood oxygenation and visual discomfort, this tends to support other evidence that a precise shade may be necessary for a beneficial clinical effect.

https://www1.essex.ac.uk/psychology/overlays/

https://www1.essex.ac.uk/psychology/overlays/faq%20OC6.htm

An NHS Orthoptic Visual Processing Difficulties (VPD) Clinic is a clinic run by Orthoptists to help children with eye problems related to or contributing to a reading or specific learning difficulty. The NHS pays optometrists a small fee for carrying out a basic eye examination. Tests for coloured overlays or coloured glasses are charged  a private fee for the detailed investigation of people with reading difficulties. Speak to your GP or optometrist for a referral to the Royal Cornwall Hospital Trust (RCHT).