Introduction to Prenatal and Infancy Development
1.1 Define the terms development, growth infancy and prenatal development
Contents of the Chapter
This Chapter is about prenatal and infant development. It is important that you know first and foremost what this is. In this unit I want you to understand what the course is all about. To do this let us start by defining some of these terms.
The terms growth and development are often used interchangeably. While they remain interrelated, the concept of growth and that of development differ essentially. These two terms represent two concepts that are characteristic of a human being from birth to death. In the discussion below I will explain the meaning of growth and development as well as prenatal and infancy periods of development.
1.2 Distinguish between growth and development
Growth refers to the increases in physical size such as changes occurring in height and weight. Between birth and age one, the average baby grows by about 20 centimetres, increasing its overall length by some 40 percent. The infant gains about 7 kilograms, tripling its birth weight while the brain doubles in size. During infancy the facial proportions change from the foetal look of the newborn to the smooth rounded-ness characteristic of the new infant.
Growth also refers to changes in body proportions. If you have observed children growing you may have realized that different parts of the body grow at different rates, at different times, leading to changes in body proportions. This is why the body proportion of an adult is different from that of a newborn. For example the newborns head is relatively larger than the adults with respect to the rest of the body. The infant’s legs and arms are also proportionately shorter than the other parts of the body when compared to an adult. Such changes in body proportion are a clear indication of growth.
Development refers to change in the level of functioning. Human beings go through many types of change and some of these changes are developmental. Development can be defined as the gradual accumulation of relatively permanent age-related changes, involving intensity and complexity of functioning.
Development is gradual. It is not something that takes place right before our eyes. Rather it is observed or measured over a period of months or years. For example if you saw a two year old child everyday you are less likely to notice developmental changes in him or her than a person who sees the child and does not see him or her again until after 3 years. Such a person is likely to comment, “My, she has really changed.” Developmental changes build upon one another. For example an infant’s creeping movements combine with advances in strength and balance toward the end of the first year to produce walking.
The other characteristic of developmental change is that it is typically irreversible under ordinary circumstances. For example when a child learns to formulate sentences, he/she may not revert to using single word utterances.
1.3 Explain principles of development cite relevant examples to illustrate the principles of development.
Principles of Growth and Development
Reflect on your development for a moment. Did you gradually grow to become the person you are, like the slow cumulative way a seedling grows in to a big tree? Were there sudden distinct changes in your growth similar to the way a caterpillar changes in to a butterfly? In other words, do you think human growth and development is like the gradual growth of a seedling into a big tree or is it like the sudden change from a caterpillar to a butterfly? These questions encourage us to consider two principles of change: Continuity of change and discontinuity of change. Continuity principle emphasizes that development involves gradual, cumulative change from conception to death. A child’s ability to walk, though seemingly on abrupt event, is the result of months of growth and practice. Discontinuity of development is the view that development involves distinct stages in the lifespan. In the development of an egg (ovum) into a baby the fertilized egg changes becoming more like a person – this development is continuous. You and I cannot say at which point in time the egg changed into a baby. The change is not drastic but gradual. The caterpillar on the other hand changes into a butterfly, a different kind of organism altogether. An example of such a change is the emergence of the ability to think abstractly about the world from not being able to do so. This is a qualitative, discontinuous developmental change.
This chapter addresses development in prenatal and infancy stages of a child’s life. In order to give you a comprehensive understanding of what the course entails, I want to introduce you to the two stages of a child’s life that are presented in this module.
1. The Prenatal period
The prenatal period refers to the period of time from conception to birth. It is a time of tremendous growth and development beginning from the moment the sperm cell from the male unites with the egg cell (ovum) from the female to form a single cell which develops in to a complete organism complete with a brain and behavioural capabilities in approximately 9 months (gestation period) at which time the period ends. At this point the organism is born. After birth the organism gets to the next stage, infancy.
Infancy is the developmental period that extends from birth to about 2 years. It is a time of extreme dependence on adults. Many changes take place in the child during this and later stages. These changes occur in different “arrears” or domains.
1.4 Examine the phenomenon of domains of change
Domains of change
These are the arrears in which growth and development occur. They include
- Cognitive domain which includes thinking, understanding and language.
- Physical domain which includes physical features like appearance, size and weight as well as motor abilities
- Social emotional domain
Significant changes occur in all these arrears. I will also introduce you to these changes in this module.
What Determines Growth And Development?
Changes that occur in human beings do not take place in a vacuum. Rather they are the product of certain factors and processes. The question of what brings about these changes has been a subject of much debate. One evidence of this is a debate referred to as the nature- nurture controversy.
It is one of the oldest controversies in the history of philosophy and human department is the nature – nurture controversy. It is all about whether behaviour is primarily determined by biological or genetic factors within the organism (nature) or by experience in the external world (nurture). This issue can be traced to the arguments of ancient Greek philosophers like Plato and Aristotle. The debate continued on and off throughout the centuries. In the modern research, the nature side was presented by maturation theorists. The nurture side was a advocated by the behavioural theorists. By 1950’s, it was realized that neither side could offer a complete explanation of human behaviour. Behaviour was found to be a product of the interaction between maturation and experience. This interaction is not a simple additive process. Hence we cannot easily determine the percentage contribution by each to the overall process of development. This interaction is complex with the contribution of each element continuously influencing and being influenced by the contributions of the other.
For example, many adults have had the experience of trying to calm a crying baby. You find that the more the baby cries, the more tense the person holding him/her becomes and the more tense the adult becomes, the more the baby cries. Can we determine how much of the infant’s distress was caused by the adult and how much was caused by the baby? Certainly no. We can only conclude that both the adult and the baby continue to influence and to be influenced by each other. Both heredity and environment combine in such an interactive fashion to influence behaviour.
You can see very clearly that since the ancient times some people have argued for heredity as the determinant of behaviour and development while others have insisted that development is governed by experience. One of the modern psychologists, Jean Piaget recognized the importance of both groups of factors.
Definition of Terms