Everyone grows and changes throughout life. But how does this development occur? In this lesson, we’ll look at the two main principles of growth and development: the Cephalocaudal Principle and the Proximodistal Principle.
Growth and Development
Imagine that you are a baby. You’ve just been born, and you don’t really understand the world around you. You can’t dress or feed yourself, you can’t talk and you can’t even sit up. All you can do is lie there and cry.
As you grow, though, you begin to be able to do more things. You can sit up and then stand. You can make noises and then talk.
Eventually, you’ll be able to fix yourself a peanut butter and jelly sandwich, learn how to solve an algebraic equation and maybe even run a marathon.Human development is the process of growth and change that every person goes through in life. People grow and develop at different rates, but mostly follow a general trajectory: people learn to crawl before they walk and to walk before they do cartwheels. Though some people may walk (or do cartwheels) earlier than others, in the end, people generally follow the same script of development.But how exactly does that developmental script play out in the human body? Let’s look closer at two theories of growth in humans: the Cephalocaudal Principle and the Proximodistal Principle.
Have you ever noticed how babies have a hard time holding their heads up? Their neck muscles can’t seem to hold the weight of the head, which is why someone who holds a baby has to support the baby’s head.
The reason babies can’t hold their own heads up is that the head is a larger percentage of their body than an adult’s head is. At birth, the head is about 25% to 30% of the body length, but by adulthood, the body has grown into the head, so that it’s only about 10% of the body length of an adult.The Cephalocaudal Principle of growth says that all other development follows from brain development. Essentially, this is the ‘top down’ view of development: as the brain grows and changes, so too does the rest of the person. The word ‘cephalo’ means brain, while the word ‘caudal’ means tail; essentially, this idea is just that the brain grows first, and that spurs on the rest of the body to grow.The Cephalocaudal Principle is usually used to explain physical development, but it can also be extended to non-physical growth.
For example, as the brain develops, so does the ability of a person to understand complex social situations. A baby doesn’t understand the nuances of an argument about how much his father works or how much money his mother spends.But as the baby grows into childhood and then into adolescence and adulthood, he begins to understand that these things are related: that his mother spends money to make herself feel better that his father works so much, and that his father works so much to earn money to support his mother’s shopping.The baby’s brain development in childhood and adolescence means that he is able to use reasoning skills to figure out the nuances of the argument. As his brain develops, so does his social intelligence.
The Cephalocaudal Principle is compelling, but it is not the only idea about how people grow. The Proximodistal Principle says that development occurs from the center outward. ‘Proximal’ means ‘near the center of the body,’ and ‘distal’ means ‘at the ends of the body,’ and that’s just how people grow, according to this theory.To understand the Proximodistal Principle, think about the way that a newborn baby moves. Lying on his back, he might kick his legs and flail his arms around. As he grows into toddlerhood, he learns to crawl, which involves controlling and coordinating the movement of his arms and legs towards a purpose. He has control over the muscles in his trunk, arms and legs.
But have you ever seen a toddler try to play piano or thread a needle? Though they can control their arms and legs, the fingers and toes are still uncoordinated. Muscular control over the extremities comes later. The Proximodistal Principle highlights this pattern of growth: first, a child has control over his trunk, arms and legs, and then he gradually obtains control over his fingers and toes. Muscular development is occurring from the center outward.
Human development is the way that people grow and change through the course of their lives. There are two major theories about how people develop: the Cephalocaudal Principle, which states that growth begins with the brain and moves down the body, and the Proximodistal Principle, which states that growth begins in the center of the body and moves outward.
After you’ve completed this lesson, you’ll have the ability to:
- Explain what human development is
- Describe the two major theories of human development