Physical development
Why is understanding physical development important?
Physical development provides children with the abilities they need to explore and interact with the world around them. A young child's physical growth first begins as muscles gain strength and children gradually develop coordination. The development of muscular control is the first step in this process.
Physical development is a vast topic; it encompasses many different tasks and abilities. Physical development can be broken into three main categories: brain development, motor development, and sensory/perceptive development.
Brain Development
The raw material of the brain is the nerve cell, called the neuron. When babies are born, they have almost all of the neurons they will ever have, more than 100 billion of them. Although research indicates some neurons are developed after birth and well into adulthood, the neurons babies have at birth are primarily what they have to work with as they develop into children, adolescents, and adults.
Physical development provides children with the abilities they need to explore and interact with the world around them. A young child's physical growth first begins as muscles gain strength and children gradually develop coordination. The development of muscular control is the first step in this process.
Physical development is a vast topic; it encompasses many different tasks and abilities. Physical development can be broken into three main categories: brain development, motor development, and sensory/perceptive development.
Brain Development
The raw material of the brain is the nerve cell, called the neuron. When babies are born, they have almost all of the neurons they will ever have, more than 100 billion of them. Although research indicates some neurons are developed after birth and well into adulthood, the neurons babies have at birth are primarily what they have to work with as they develop into children, adolescents, and adults.
Newborns' brains allow babies to do many things, including breathe, eat, sleep, see, hear, smell, make noise, feel sensations, and recognize the people close to them. But the majority of brain growth and development takes place after birth, especially in the higher brain regions involved in regulating emotions, language, and abstract thought. Each region manages its assigned functions through complex processes, often using chemical messengers (such as neurotransmitters and hormones) to help transmit information to other parts of the brain and body.
The Growing Baby's BrainBrain development, or learning, is actually the process of creating, strengthening, and discarding connections among the neurons; these connections are called synapses. Synapses organize the brain by forming pathways that connect the parts of the brain governing everything we do—from breathing and sleeping to thinking and feeling. This is the essence of postnatal brain development, because at birth, very few synapses have been formed. The synapses present at birth are primarily those that govern our bodily functions such as heart rate, breathing, eating, and sleeping. |
The development of synapses occurs at an astounding rate during children's early years, in response to the young child's experiences. By the time children are 3, their brains have approximately 1,000 trillion synapses, many more than they will ever need. Some of these synapses are strengthened and remain intact, but many are gradually discarded. This process of synapse elimination is called pruning, and It is a normal part of development. By the time children reach adolescence, about half of their synapses have been discarded, leaving the number they will have for most of the rest of their lives. Brain development continues throughout the lifespan. This allows us to continue to learn, remember, and adapt to new circumstances.
Another important process that takes place in the developing brain is myelination. Myelin is the white fatty tissue that insulates mature brain cells by forming a sheath, thus ensuring clear transmission across synapses. Young children process information slowly because their brain cells lack the myelin necessary for fast, clear nerve impulse transmission. Also, like other neuronal growth processes, a child's experiences affect the rate and growth of myelination, which continues into young adulthood.
By the age of 3, a baby's brain has reached almost 90 percent of its adult size. The growth in each region of the brain largely depends on receiving stimulation, which spurs activity in that region. This stimulation provides the foundation for learning.
An important aspect of the human brain is its plasticity. The term plasticity to describes the brain's ability to change in response to repeated stimulation. The extent of a brain's plasticity is dependent on the stage of development and the particular brain system or region affected. For instance, the lower parts of the brain, which control basic functions such as breathing and heart rate, are less flexible than the higher functioning cortex, which controls thoughts and feelings. While cortex plasticity may lessen as a child gets older, some degree of plasticity remains. In fact, this brain plasticity is what allows us to keep learning into adulthood and throughout our lives.
The developing brain's ongoing adaptations are the result of both genetics and experience. Our brains prepare us to expect certain experiences by forming the pathways needed to respond to those experiences. For example, our brains are "wired" to respond to the sound of speech; when babies hear people speaking, the neural systems in their brains responsible for speech and language receive the necessary stimulation to organize and function. The more babies are exposed to people speaking, the stronger their related synapses become. If the appropriate exposure does not happen, the pathways developed in anticipation may be discarded. This is sometimes referred to as the concept of "use it or lose it." It is through these processes of creating, strengthening, and discarding synapses that our brains adapt to our unique environment.
The ability to adapt to our environment is a part of normal development. Children growing up in cold climates, on rural farms, or in large sibling groups learn how to function in those environments. But regardless of the general environment, all children need stimulation and nurturing for healthy development. If these are lacking or if a child's caretakers are indifferent or hostile, the child's brain development may be impaired. Because the brain adapts to its environment, it will adapt to a negative environment just as readily as it will adapt to a positive one.
Motor Development
Due to the immaturity of the human nervous system at the time of birth, children grow continually throughout their childhood years. Many factors contribute to the ability and the rate that children develop their motor skills. Uncontrollable factors include: genetic or inherited traits and children with learning disorders. A child born to short and overweight parents is much less likely to be an athlete than a child born to two athletically built parents. Controllable factors include: the environment/society and culture they are born to. A child born in the city is much less likely to have the same opportunities to explore, hike, or trek the outdoors than one born in the rural area. For a child to successfully develop motor skills, he or she must receive many opportunities to physically explore the surroundings.
Another important process that takes place in the developing brain is myelination. Myelin is the white fatty tissue that insulates mature brain cells by forming a sheath, thus ensuring clear transmission across synapses. Young children process information slowly because their brain cells lack the myelin necessary for fast, clear nerve impulse transmission. Also, like other neuronal growth processes, a child's experiences affect the rate and growth of myelination, which continues into young adulthood.
By the age of 3, a baby's brain has reached almost 90 percent of its adult size. The growth in each region of the brain largely depends on receiving stimulation, which spurs activity in that region. This stimulation provides the foundation for learning.
An important aspect of the human brain is its plasticity. The term plasticity to describes the brain's ability to change in response to repeated stimulation. The extent of a brain's plasticity is dependent on the stage of development and the particular brain system or region affected. For instance, the lower parts of the brain, which control basic functions such as breathing and heart rate, are less flexible than the higher functioning cortex, which controls thoughts and feelings. While cortex plasticity may lessen as a child gets older, some degree of plasticity remains. In fact, this brain plasticity is what allows us to keep learning into adulthood and throughout our lives.
The developing brain's ongoing adaptations are the result of both genetics and experience. Our brains prepare us to expect certain experiences by forming the pathways needed to respond to those experiences. For example, our brains are "wired" to respond to the sound of speech; when babies hear people speaking, the neural systems in their brains responsible for speech and language receive the necessary stimulation to organize and function. The more babies are exposed to people speaking, the stronger their related synapses become. If the appropriate exposure does not happen, the pathways developed in anticipation may be discarded. This is sometimes referred to as the concept of "use it or lose it." It is through these processes of creating, strengthening, and discarding synapses that our brains adapt to our unique environment.
The ability to adapt to our environment is a part of normal development. Children growing up in cold climates, on rural farms, or in large sibling groups learn how to function in those environments. But regardless of the general environment, all children need stimulation and nurturing for healthy development. If these are lacking or if a child's caretakers are indifferent or hostile, the child's brain development may be impaired. Because the brain adapts to its environment, it will adapt to a negative environment just as readily as it will adapt to a positive one.
Motor Development
Due to the immaturity of the human nervous system at the time of birth, children grow continually throughout their childhood years. Many factors contribute to the ability and the rate that children develop their motor skills. Uncontrollable factors include: genetic or inherited traits and children with learning disorders. A child born to short and overweight parents is much less likely to be an athlete than a child born to two athletically built parents. Controllable factors include: the environment/society and culture they are born to. A child born in the city is much less likely to have the same opportunities to explore, hike, or trek the outdoors than one born in the rural area. For a child to successfully develop motor skills, he or she must receive many opportunities to physically explore the surroundings.
Early movements made by very young infants are largely reflexive. An infant is exposed to a variety of perceptual experiences through the senses. A reflex is a muscle reaction that happens automatically in response to a certain type of stimulation. Certain sensations or movements produce specific muscle responses. Many infant reflexes disappear as the child grows older, although some remain throughout adulthood. The presence of an infant reflex after the age at which the reflex normally disappears can be a sign of brain damage or damage to the nervous system.
As an infant is exposed to a variety of perceptual experiences through the senses, gradually, the infant learns that certain involuntary, reflexive movements can result in pleasurable sensory experiences. The infant will attempt to repeat the motions voluntarily in order to experience the pleasurable sensation. This is the beginning of motor skills development. There are two categories of motor skills: gross motor skills and fine motor skills. |
Gross motor skill requires the use of large muscle groups to perform tasks like walking, balancing, crawling. The skill required is not extensive and therefore are usually associated with continuous tasks. Much of the development of these skills occurs during early childhood. The performance level of gross motor skill remains unchanged after periods of non-use.
Fine motor skill requires the use of smaller muscle groups to perform tasks that are precise in nature. Activities like playing the piano and playing video games are examples of using fine motor skills. Generally, there is a retention loss of fine motor skills over a period of non-use. Discrete tasks usually require more fine motor skill than gross motor skills.
For a chronology of motor skill development see "A Guide To Your Child’s Gross & Fine Motor Development," a book published by Brooks Rehabilitation. The .pdf version of the file can be downloaded from the link below.
Fine motor skill requires the use of smaller muscle groups to perform tasks that are precise in nature. Activities like playing the piano and playing video games are examples of using fine motor skills. Generally, there is a retention loss of fine motor skills over a period of non-use. Discrete tasks usually require more fine motor skill than gross motor skills.
For a chronology of motor skill development see "A Guide To Your Child’s Gross & Fine Motor Development," a book published by Brooks Rehabilitation. The .pdf version of the file can be downloaded from the link below.
motor-skills.pdf | |
File Size: | 6384 kb |
File Type: |
Sensory and Perceptive Development
Sensory and perceptive development refers to one's development of the five senses: vision, hearing, taste, smell, and touch. As we will explore each of the five senses we will mostly focus on the senses of infants as that is when they experience the bulk of their growth. We will also explore each sense as separate sections, except for taste and smell which are inherently linked.
Vision
At birth, a baby has a fairly limited range of visual focus, from 8 to 12 inches, which is just the right distance for nursing or for a diaper change! Vision improves rapidly over the next six months. At first, babies seem to explore areas with the greatest visual contrast, such as black and white mobiles. At one month, babies scan the contrasting areas of a person's face, such as angles, edges of the hairline, and shining eyes. Infants are naturally attracted to human faces. When presented with the choice of looking at a bull's-eye, printed patterns, brightly colored disks, or the human face, they choose the face. Infants a few months old become distressed if a teacher's face is still and not expressive.
Hearing
Auditory functioning is excellent even before birth. A 3-day-old infant can distinguish her mother's voice from that of a stranger-and researchers have discovered that the baby prefers the mother's voice. Infants do startle at loud sounds. When even a few months old, infants are sensitive to an angry voice. They will frown and look upset. They can also differentiate between sounds in all the languages of the world. So, for example, infants in Japan hear the difference between "L" and "R," although this distinction is lost on speaking adults in the Japanese culture. However, by the end of the first year, babies no longer can identify sounds that are not in their native language.
Taste and Smell
Taste and smell discriminations also seem to be "wired in." Newborn infants will turn away from a strong vinegar smell on a cotton swab. They'll smack their lips at the scent of a ripe banana. Infants pucker their lips at sour tastes and protrude their tongues at bitter tastes. They have twice as many receptors for sweet at the back of the mouth as do adults. A newborn exhibits increased heart rate and sucks more slowly if given a bit of sugar water. Babies love sweet tastes.
Touch
Babies are primed to respond to gentle touch. They wriggle with joy when tenderly touched with long strokes of the palms. They have a greater density of skin receptors in relation to amount of skin surface. Hurtful touch, such as a needle prick on the heel to draw blood to test for PKU, for example, elicits a sound of pain.
Sensory and perceptive development refers to one's development of the five senses: vision, hearing, taste, smell, and touch. As we will explore each of the five senses we will mostly focus on the senses of infants as that is when they experience the bulk of their growth. We will also explore each sense as separate sections, except for taste and smell which are inherently linked.
Vision
At birth, a baby has a fairly limited range of visual focus, from 8 to 12 inches, which is just the right distance for nursing or for a diaper change! Vision improves rapidly over the next six months. At first, babies seem to explore areas with the greatest visual contrast, such as black and white mobiles. At one month, babies scan the contrasting areas of a person's face, such as angles, edges of the hairline, and shining eyes. Infants are naturally attracted to human faces. When presented with the choice of looking at a bull's-eye, printed patterns, brightly colored disks, or the human face, they choose the face. Infants a few months old become distressed if a teacher's face is still and not expressive.
Hearing
Auditory functioning is excellent even before birth. A 3-day-old infant can distinguish her mother's voice from that of a stranger-and researchers have discovered that the baby prefers the mother's voice. Infants do startle at loud sounds. When even a few months old, infants are sensitive to an angry voice. They will frown and look upset. They can also differentiate between sounds in all the languages of the world. So, for example, infants in Japan hear the difference between "L" and "R," although this distinction is lost on speaking adults in the Japanese culture. However, by the end of the first year, babies no longer can identify sounds that are not in their native language.
Taste and Smell
Taste and smell discriminations also seem to be "wired in." Newborn infants will turn away from a strong vinegar smell on a cotton swab. They'll smack their lips at the scent of a ripe banana. Infants pucker their lips at sour tastes and protrude their tongues at bitter tastes. They have twice as many receptors for sweet at the back of the mouth as do adults. A newborn exhibits increased heart rate and sucks more slowly if given a bit of sugar water. Babies love sweet tastes.
Touch
Babies are primed to respond to gentle touch. They wriggle with joy when tenderly touched with long strokes of the palms. They have a greater density of skin receptors in relation to amount of skin surface. Hurtful touch, such as a needle prick on the heel to draw blood to test for PKU, for example, elicits a sound of pain.