Vision is the supreme sense of man. Seeing is not a separate, independent function. It is profoundly integrated with the total action system: posture, manual skills, intelligence and personality (Gesell).

Vision is an extremely complex process in which the eye receives light-based information and converts it into a bioelectric message that is transmitted to different areas of the brain where it is analysed and integrated with other types of information, and then processed and interpreted. In addition to sensory information from the eye other sensory inputs, primarily from balance and the vestibular system of the inner ear, that provide the visual system with information that it uses to construct optimal Vision. Therefore, Vision depends on the integrity of the receptor organ, the eye, and the cerebral pathways and structures involved in the complex process of VISION.

It is known that almost 80% of sensorial information coming into the brain comes in through the vision process, meaning that what a person perceives, remembers, understands depend, to a great extent on the quality of the person’s visual system.


We must not confuse SIGHT and VISION.

When we talk of SIGHT, in general we are referring to the capacity of distinguishing small details and no information is obtained on how much effort is used or if the information is processed efficiently and remembered correctly. Whilst essential, this capacity is not sufficient in itself to produce good VISION.

The Vision process involves a series of skills that are learned from birth and developed in parallel with the processes of hearing, walking and speaking. We need between 8 and 12 years of our lives for our Vision to fully develop.

Some of these skills are:

  • Visual Acuity: fine image discrimination in near and far vision.
  • Ocular Motility: the eye movements made when following a moving object or jumping from one space to another.
  • Accommodation: focusing at different distances.
  • Binocularity: coordinating and aligning the eyes to obtain a single image.
  • Stereopsis: perceiving images in three dimensions.
  • Visuomotor integration: coordinating ocular movement with hand movement.
  • Spatial Vision: visual recognition of space and of space-time relationships.
  • Visual Auditory Integration: coordinating auditory information with visual information.
  • Visual Perception: interpreting visual information, recognising images, visual memory, visualisation, etc.

Children use Vision to determine: colours, shapes, thicknesses, textures, spatial limits, speeds and rhythms. They visualise words, sounds, images and concepts and Vision helps them to project themselves in space and time.

Everything that children see, how they interpret what is around them, and their speed and skill of visual recognition determines the majority of daily activities.

Visual development does not occur in isolation, but rather in parallel with the individual’s motor development.

For example, babies will initially pay attention to nearby objects (mother, father, their hands, bottle, etc.) and later, as their motor development enables them to start moving around the room, they will begin looking for more distant objects. Furthermore, Vision enables them to be aware of the space they occupy, of their position within it, and of the spatial relationship between objects.

All these experiences will enable children to balance their focusing system, coordinate and refine the accuracy of their eye movements, be aware of spatial perception, and to interpret the visual information they are receiving correctly. Therefore, one parental task should be to allow their child freedom of movement and exploration, via appropriate stimuli, the experiences that children need to acquire basic concepts such as distances, textures, sizes, shapes, etc., all of which are essential for later and more complex learning processes such as reading and writing. When an child has not established the necessary neurological connection then disorders or deficits will occur in the way visual information is processed.

At the present time, the visual demands in our society are extremely high. The speed and the competitive nature of modern living and having to spend many hours sitting in front of a computer screen make learning and attention problems, as well as performance problems in adult life, relatively frequent. Failures are often due to a poor visual perception and the processing of visual information.

The different areas involved in the visual process can be assessed to determine which parts need to be learned or “relearned”. This is possible using to a series of tests performed by a Behavioural Optometrist who, when necessary, can also design a therapy plan with the aim of helping the individual to perceive, processes and understand visual information more efficiently.

The following visual hygiene suggestions can help to decrease vision problems. However, they do not resolve them totally, but they can contribute towards obtaining higher performance and less visual fatigue:

  1. Sit correctly: with feet flat on the floor and back straight.
  2. Furniture must be suitable: the chair must be height adjustable and the desk must be on an inclined plane of between 15 and 20°. A child needs furniture specially designed for children.
  3. Lighting is extremely important; reading and studying should be done beneath one light source mounted in the ceiling and another angle lamp mounted directly on the work surface that does not shine directly into the eyes, does not dazzle and does not throw shadows when writing. Locate the beam of the light to the left if the person is right-handed and to the right if they are left-handed.
  4. The reading distance distance must not be too short. The ideal distance is approximately from the elbow to the first phalanx bone of the middle finger.
  5. When reading, the forearms must be resting on the work surface.
  6. Reading must not be done with the head moving, but with the eyes alone. If this is not the case, it could be a sign of a vision problem.
  7. If possible, the desk, should be located in front of a window in order to be able to look into the distance every so often.
  8. Interrupt prolonged close up visual activity, by raising your head or changing your posture.
  9. As far as TV and videogames are concerned, glare must be avoided, it/they must never be watched/played with the light switched off, nor too close, or lying on the floor, and for no longer than 1 hour a day.
  10. Their diet should be rich in vitamin A (milk, carrots, plums, egg yolks, etc.), vegetables and fruit.
  11. 11. Trips to the country and/or to free and open spaces are recommendable.