Visual Stress

Visual Stress is reading difficulty resulting from either optical visual problems (physical causes) or visual processing disorders (cognitive/neurological causes).

Optical problems often result from simple near or far sightedness. Mental processing problems are often the result of visual stress

Vision in Learning

Learning is accomplished through complex and inter-related processes, of which vision is one. There are many component parts to vision, of which clarity of sight is just one.

An inefficient visual system may lead to;

  • Losing one’s place when reading
  • Difficulty copying off the board
  • Limited concentration
  • Tiredness
  • Not reaching learning potential
  • Frustration and so becoming disruptive
  • Poor handwriting

A basic sight test or general eye examination will do a good job of ensuring clear sight and healthy eyes, but does not necessarily look in-depth at the visual factors that can have an affect on reading.
Research at Essex University has found that 1 in 5 children will demonstrate an improvement in reading speed through the use of colour (overlay or precision tint).

Visual Factors Affecting Reading

  • Clarity of Sight (Visual Acuity) – What you see and how clear it is.
  • Accommodative Function – How accurately you focus on what you are looking at, how well you maintain this focus and how quickly you can change your focus. Inefficiencies will lead to difficulties copying off the board, grinding to a halt after a limited spell of reading, or difficulty with smaller text.
  • Binocular Vision – How well the eyes work together as a team and how well they continue to work when the system is stressed. Even subtle problems can stop a child from reaching their potential. Often causes loss of place or missing words/doubling back.
  • Ocular Movement Skills – How accurately the eyes move includes pursuit tracking and convergence. These are key factors to following the line and locating the next line. Difficulty can affect the flow of reading.
  • Pattern Glare Sensitivity – Ability to cope with black lines on white backgrounds (ie text). Also known as Mearles-Irlen or scotopic sensitivity, sufferers have a range of symptoms including losing one’s place, headache, eyestrain, eye fatigue. Some can be extremely sensitive and can lead to great discomfort and thus a lack of interest in reading. Reducing pattern glare (usually with coloured overlays or precision tints) can have a dramatic effect on reading skills.
  • Eye Dominance – Unstable eye dominance may cause loss of place. Cross dominance may be a factor in mixing up letters (saw or was) and letter reversals.
  • Visual Field and Peripheral Awareness – The vision around you and how you integrate information in it with your central vision.
  • Fusional Reserves – Eye Muscle strength and flexibility.
  • Visual Centring – Relating where you are in your visual space and relating this with other objects


Visual Evaluation

The initial assessment comprises of a detailed bespoke visual evaluation based on the individual’s difficulties.

The Visual Evaluation comprises of additional tests (assessing the components of vision) not included in a standard eye examination.
This may be why a client has always ‘done well’ in a basic NHS sight test yet still has a vision-related learning problem.

Findings and options of treatment programmes if applicable are discussed with the client (and parent.)

Vision Therapy

Vision Therapy does not treat learning disabilities or dyslexia. Vision Therapy is a treatment programme to improve visual efficiency and visual processing, thereby allowing the person to be more responsive to educational instruction. It should be part of a multi-disciplinary approach to learning.

Vision is the dominant sense; by improving visual efficiency we are often able to ‘unlock’ the door to reaching reading potential. However, although in many cases the door may be unlocked by vision therapy, it still requires the client to want to make the journey into the room.

Vision therapy may comprise of lenses (corrective/ training), colorimetry (coloured overlays/precision tints) and/ or a course of tailor-made one-to-one exercises.