The ‘Developmental Pyramid’
See also: https://visionmechanic.net/the-human-visual-developmental-pyramid/
(Extract from ‘Dr. B’s Guide to Child Vision, Learning, and Development’ series: Fundamentals 1: Learning Mechanics)
It’s helpful to look at human development as the construction of a pyramid, with basic (or core) functions at the base, and the more refined and complex functions at the top. These core, or base, functions support the development of higher cognitive and motor skills during early development, and then they continue to contribute to the quality of those functions throughout a child’s life.
While the pyramid analogy is a good one, the reader should not be tricked into thinking that later (higher) levels of development come only after the base is complete. In fact, like the Great Pyramids, a child’s body develops beginning with the base, but the higher levels begin soon after: All systems are present and growing very early in development. The core structures and functions required to simply maintain life arrive first: basic circulation, nervous system, digestive tract, and so on. The senses themselves arrive not long after that: Once these arrive, more advanced mental and motor processes also become possible. For the greater part of a child’s early development, all systems develop together and at the same time, but mature at different rates. Vision for its part can be represented at the top of the pyramid – with mature visual perception, we can ‘smell’, touch, understand, and manipulate objects without ever even touching them. Vision is also represented at the bottom of the pyramid as a very rudimentary function that allows for basic targeting and object avoidance.
Where we begin, our pyramid base, is the point where the child is born. Basic motor and reflex systems are in place to deal with surviving, finding food and comfort, and expressing discomfort. The senses are present and, as newborns, we are especially familiar with our senses of hearing and smell, but touch, balance, vision all need to move to a new level of control and awareness to be useful. Shortly after this, the senses begin to integrate with one another as they ‘turn on’, and this allows complex responses to environmental challenges, like sitting up and crawling, reaching and grabbing.
The middle level of the pyramid is where we find the senses are largely ‘on’ and integrated, but not practiced or honed – somewhere between 18 and 36 months. Kicking a ball or making noise with a musical instrument would be possible, but only as mirroring or a rudimentary voluntary level. Targeting is possible by both gross-motor systems (arms and legs) and finer motor systems as well (fingers/hands, toes/feet, eyes), but again, fine targeting is not yet possible. The child is also more able to focus attention, such as to visual, auditory, or tactile and do so at will: The mind begins to be able to move from random experiences and responses to external events (peripheral awareness), to the ability to pay attention to something, what we will call ‘focal’ or ‘central’ attention.
The top level of the developmental pyramid sees the child fully able to guide behaviour, make choices that matter, and pay attention to what he is doing or what is happening around him. This will generally arise between 48 and 60 months. He has the physical capacity to read, to scan across the page in proper sequence without losing his place. He can look and listen for things, meaning he can attend to specific stimuli against a noisy background – and maintain that attention. It is also possible to move attention from very precise focal attention to broad scanning and ‘stand-by’ modes of operating, and to do this at will. All the tools needed to function as an adult are there, and need only to be used, practiced.
This concept of the mechanical side of the child is helpful in that it can assist in guiding diagnosis and advise treatment planning. If for example, a child seems to have no trouble with gross-motor control, balance and coordination, it does not make sense to spend too much time working on these functions. Rather, we should concentrate our efforts in assessing and remediating higher-level targeting and cognitive skills. Likewise, if the child struggles with reading (a very high level integrative function) but shows difficult gross-motor coordination and balance, these ‘low end’ functions should be addressed early in therapy; simply throwing more reading exercises at the child should not be expected to provide much benefit on their own and may prove too difficult and frustrating for the child who is not yet ready to manage symbolic language requiring strong spatial awareness and visual function.
Also, when a child shows signs of motor skills deficits, this can mean either the skills were never there, or that that they were there and are now missing. In the case of brain injury, for example, it is possible to see regressions, or ‘backward steps’ in behaviour where a child can no longer perform at a high level, and instead will revert to old habits and responses – a step down on the developmental pyramid. In either case, a good therapist will be able to help, but must approach the situation very carefully depending on the cause of the deficit, be it developmental, functional, or resulting from trauma or disease. Understanding how sensory and motor systems interact and support one another helps to find meaningful solutions that emphasize a child’s individual needs.
