6.4 Examine the concept of Motor Development in the context of infant growth and development
Motor development deals with control of movement of various parts of the body. At birth the baby is a dependent creature who stays in one spot when laid down. As the primary motor area of the brain matures the motor skills emerge. The sequence of motor skills is generally the same. At the beginning the motor abilities follow the same cephalocaudal and proximodistal patterns as in physical growth e.g. the infant lifts the head, then their shoulders, before they can sit up. They sit up before they can stand.
The specifics of arm, hand and finger control follow the proximodistal pattern. At birth infants have a reflexive grasp, but they have no control of it. Then they start moving their arms and hands when they see dangling objects – but they can’t hit them until they are about 3 months old. They still cannot grab the object because they close their hands too soon or too late. By 6 months, most babies can reach, grab and hold on to dangling objects. They still have a new problem – they can’t let go. A toy seems stuck in their hands until they lose interest in it then their hands relax and the toy drops out. Letting go is mastered by about 7 months. Another activity to be mastered is picking about small objects by fingers. At first babies use their whole hand usually the palm and slowly they learn to hold with fingers by about one year of age.
Most babies first learn to move from place to place by lying on their stomachs and pulling themselves ahead with their arms. Later they learn to crawl on hands and knees at around 7 to 8 months. Some babies do not crawl at all.
On average a child can stand with support at 7 months, can walk with support at 9 months and can walk unassisted at 12 months. In recognition of their walking accomplishment – the babies at this age are called toddlers- because of the way they use their legs toddling from side to side. Since their heads and stomachs are relatively heavy and large, they spread out their little legs for stability.
One-year olds cannot run. They fall frequently, their head gets too far a head of the legs when they try to run and hence they keep falling. By age 2 years, most children can walk and run quite well still placing feet wide apart.
Note that although healthy infants develop the same motor skills in the same sequence there are variations in timing. The age at which these skills are acquired varies from infant to infant.
Can Motor Control in Infants be facilitated?
Research has shown that training will facilitate the development of motor skills. Charles Super (1976) observed that a Kenyan tribe, the Kipsigis, train their very young infants to sit and to walk. Beginning at one month, mothers play with their babies by bouncing them on the laps, prompting the stepping reflex. Consequently, the stepping reflex does not disappear as it does with infants in other cultures. Beginning at six months, Kipsigis mothers prop their infants into sitting positions to encourage sitting. Kipsigis infants were observed to sit, stand, and walk approximately one month earlier than American babies. This does not mean that Kipsigis children have some genetic advantage not shared by other cultures. The Kipsigis babies show early acquisition of skills that are trained in the culture but not of skills that are not trained (Super, 1976).
6.5 Discuss the changes in Bones and Muscles in the developmental stages of an infant
Changes in Bones and Muscles
Changes in the nervous system are paralleled by changes in other body structures, including bones and muscles. However, changes in bones and muscles occur gradually from infancy through adolescence.
The hand, wrist, ankle and foot all have fewer bones at birth than they will have at full maturity. For example, in an adult’s wrist there are nine separate bones. In the one-year old, there are only three. The remaining six develop over the period of childhood, with complete growth by adolescence.
The skull of a newborn is made up of several bones separated by spaces called fontanels. Fontanels allow the head to be compressed without injury during the birth process, and they also give the brain room to grow. In most children, the fontanels are filled in by bone by 12 to 18 months, creating a single connected skull bone.
All of the infant’s bones are also softer, with higher water content, than adults’ bones. The process of bone hardening is called ossification. It occurs steadily from birth through puberty, with bones in different parts of the body hardening in a sequence that follows the typical proximodistal and cephalocaudal patterns. For example, bones of the hand and wrist harden before those in the feet.
Bone hardening has some direct practical relevance. Soft bones are clearly needed if the foetus is going to have enough flexibility to fit into the cramped space of the uterus. But because of this flexibility the newborn human is relatively helpless. Newborns cannot even hold their own heads up, let alone sit or walk. As the bones stiffen, the baby is able to manipulate his body more surely, which increases the range of exploration he can enjoy and makes him much more independent.
Muscle fibers are initially small and watery, becoming longer, thicker, and less watery at a fairly steady rate until adolescence. The sequence is again both proximodistal and cephalocaudal. So the baby gains muscle strength in the neck fairly early, but does not have enough muscle strength in the legs to support walking until some months later.
6.6 Highlight the important role of nutrition to the growth and development of an infant
Adequate nutrition is a pre-requisite for the changes in size, shape, brain development and mastery of skills. At first, infants are unable to eat or digest food, but their rooting, sucking, swallowing and breathing reflexes enable them to consume the quantities of liquid nourishment they need.
Appropriate nutrition and feeding habits help to ensure healthy development of the infant. Infant’s nutrient needs differ from those of adults in both quantity and proportion.
Is Breast Milk Important?
Breast milk alone will meet the infant’s needs during the first 4 to 6 months. In these early months breast milk is the most ideal infant food. It has several advantages over other alternatives:
- It is sterile, that is, not contaminated.
- It’s at body temperature. It is not too cold or too hot.. Thus it does not need to be heated or cooled for consumption.
- It contains proper nutrients needed by the growing baby for instance it contains more iron, vitamin C and vitamin A than cow’s milk
- It contains antibodies that provide the infant some protection against any disease that the mother herself has had, or has been inoculated against such as chickenpox, smallpox, tetanus etc.
- It’s more digestible than cow’s milk or formula – hence breast fed babies have fewer allergies and digestive upsets than bottle fed babies