It is thought that the problem of Developmental Co-ordination Disorder may be caused by failure of the Central Nervous System adequately to interpret, integrate and process the information required to produce an appropriate response. This may be a motor response, such as reacting to save ourselves from falling, or a conceptual one such as recognising a complete object from the sensory information received.

In order to understand this, we need to consider, very simply, how the normal Central Nervous System (CNS) works. It takes in, interprets, sorts out and connects sensory information, organises it and processes the response. All this goes on automatically, below the level of awareness.

‘Sensory Information’ needs further explanation. There are the more obvious senses, which we all know about, such as hearing, vision, taste and smell. However, every bit as important is the input which we rarely think about Tactile, Proprioceptive and Vestibular information.

To explain more fully:

Tactile refers to touch. There are two basic parts to our tactile systems: one responds to light or unexpected touch and protects us from potential danger. The other is discriminatory and helps us to gain information about the quality of what we feel hard or soft, rough or smooth, etc.

Proprioceptive. Our proprioceptors give us information from muscles, ligaments, tendons and joints and therefore let us know the position of our body parts and our position in space, without our needing to look. They also help with the detection of force resulting in the ability to achieve force control.

Vestibular refers to our balance system. This lets us know our relationship to gravity and our body position in space, e.g. whether the body or environment is moving, how fast we are moving, which way up we are, etc. Our Vestibular Systems along with Proprioceptive System are responsible for maintenance of posture.

All these senses must receive information accurately and then the CNS must interpret and integrate it in order for us to function normally. For example, not only do we need adequate vision but also our systems need to interpret what we see and then integrate it with information from our other senses. This applies to all types of sensation.

Therefore, if a child has difficulty with several, or occasionally all, of these processes, he/she will have considerable difficulty with writing. The same applies to any other process from fairly basic motor tasks such as jumping, hopping, etc through to more complicated tasks such as riding a bicycle or tying shoelaces, to the most sophisticated areas of academic learning.

A simple way to look at it is to imagine the brain as being a bit like a telephone exchange where, in the child with DCD, the wiring is incomplete, inefficient or crossed. The result, to use a another metaphor, has been described as being ‘something like a rush-hour traffic jam’.

Sometimes interpretation and integration seem inadequate; sometimes different types of sensory input seem to be ‘at odds’ with one another. An example of the adverse way in which normal people react to conflicting stimuli is travel or seasickness, where if we watch the horizon we feel better than we do if we look at something that is stationary, e.g. a map in the car. In the former instance our vestibular and visual systems are giving us the same information: we are moving. In the latter, they are ‘at odds’ – our vestibular systems will give us signals that we are moving, but our vision is interpreting something static. Similarly, in a treatment session, a child with visual perceptual problems closed his eyes and produced much better ‘patterns’ on a board; he was relying on his very adequate tactile and proprioceptive systems and eliminating the conflicting information from his poor visual perception.

In order to move on from movement to learning, there are further requirements based on the preceding ones. Some of these are:

For movement and learning to occur, our brains need to ‘put together’ all the preceding factors efficiently and eventually automatically. It seems that in some children, the process does not work entirely efficiently. If we take a complex process like writing and analyse it, we can see how many components are required. Some of these are:

In the child with DCD problems it seems that these early functions are not complete. There are many reasons for this, such as:

• Inadequate or inaccurate interpretation of sensory information leading to limited or inaccurate information to the Central Nervous System on which to base further experience.
• Avoidance of those things that are difficult or threatening, also limiting experience and opportunity to develop more skilled movements.
• Limited speech and language development because we use language and movement to support one other.
• Limited exposure to natural movement experiences.
• Poorly integrated primitive reflexes – adversely affecting normal movement, etc.

When this groundwork is not complete, movement continues to be conscious (or thought through) rather than automatic, and consequently the child is less able to cope with and think about the more sophisticated complex parts of tasks.

It has been said that, “there is nothing less efficient than the cortex (or ‘thinking’ part of the brain) thinking its way through movement”. In many DCD children, this is precisely what appears to be happening, having a considerable effect on sophisticated skills and academic learning.

Finally, no two children are exactly the same, and there are many different sorts of Motor and Specific Learning Difficulties. The child’s problems with perception and processing can lie in several different areas.

• The problem may be mainly related to balance and posture, and sometimes associated with bilateral skills and direction, etc.
• It may be Dyspraxia and therefore mainly associated with movement planning, affecting everything from organising gross movement to coping with the complex skill of writing, and often including organisation of self in relation to the environment.
• It may be mainly visual perceptual and therefore often affecting drawing, writing, etc.
• Sometimes a child may have difficulty in regulating his response to sensations in the environment, such as touch or movement. The adverse responses may then present as poor behaviour or difficulty with attention.

Frequently there is a combination of more than one of these possibilities.

Sometimes, sadly, a child has generalised problems affecting all these areas and often (though not always) this may be associated with restlessness and poor attention. In these cases, the child who obviously has no compensating area of strength may gain less from treatment.

Whatever the problem, the result is a child with co-ordination problems, specific learning difficulties and often speech and language problems; a child whose self-esteem is usually low, who lacks confidence and who is often a lonely child, may develop strong opting out strategies and other behavioural or emotional problems.

In short, children with these difficulties need understanding and positive help if life is not to become frustrating and unhappy for family, teachers and, most of all, themselves.

The Dyspraxic Child