Session 4 & 5: Physical and Motor Development in Infants & ToddlersManju Nair

Body Growth

Newborns gain around 28 grams/ 1 ounce of weight a day for the first two months.

450 grams per month after that.

A new born’s length increases by 30% by 5 months of age and 50% by 12 months.

Ethnic differences and gender differences exist in size.

The Cephalocaudal Trend

Growth occurs in a top down manner i.e from the head downwards. This is true especially of the first few months of life.

Motor development of the upper parts of the body precedes that of the lower parts.

Changes in body proportion from birth to adulthoodwww.mrothery.co.uk/ images/growth.gif

The Proximodistal Trend

Growth begins at the centre of the body and proceeds to the extremities. E.g. shoulder, then elbow, then wrist and finally fingers.

Motor development too follows this trend.

Skeletal Growth

Body size alone is not an indication of physical maturity and age.

The best way to estimate age is through the skeletal age; a measure of the bone development.

Skull Growth

Skull growth is rapid because of the large increase in the brain size in the first 2 years of life.

The bones of the skull are separated by six gaps called ‘soft spots’ or fontanels.

The skull bones fuse together by 12 to 18 months and the soft spots disappear.

fontanelshttp://www.google.com/imgres?imgurl=http://www.childclinic.net/neurology/fontanel.gif&imgrefurl=http://www.childclinic.net/neurology/fontanel1.html&usg=__6uVSnSKkH0tiGTpzmAuNmWth82s=&h=262&w=599&sz=40&hl=en&start=7&zoom=1&tbnid=qngWmpLcrk-BcM:&tbnh=59&tbnw=135&prev=/images%3Fq%3Dfontanels%26um%3D1%26hl%3Den%26client%3Dsafari%26sa%3DN%26rls%3Den%26biw%3D1024%26bih%3D584%26tbs%3Disch:1&um=1&itbs=1&ei=bvf2TNf5G4vBcYrV-IMF

Appearance of Teeth

An infant’s first teeth usually appears between 4 to 6 months of age.

By age 2, the child has 20 teeth.

The lower front teeth usually appears by 5 to 9 months and upper front teeth by 8 to 12 months.

Nutrition has a strong effect on growth especially breast milk in infancy. Breast milk provides the following: 1] correct balance of fat and protein. 2] nutritional completeness. 3] protection against disease. 4] protection against faulty jaw development and tooth decay. 5] digestibility. 6] smoother transition to solid foods.

Wrong food preferences, malnutrition [marasmus or kwashiorkor], and obesity are some factors that affect growth.

Effect of Nutrition

Brain Development

The brain is nearer to its adult shape and size at birth than any other part of the body.

The largest area of the brain is called the cerebral cortex and is responsible for receiving and processing sensory information, thinking, language and so on.

The largest structure in the brain.

Accounts for 85% of brain’s weight.

Looks like a shelled walnut and accounts for the greatest number of neurons and synapses.

It is the last to stop growing and is responsible for the unique intelligence of the human brain.

The Cerebral Cortex

The Cerebral Cortex

http://0.tqn.com/d/psychology/1/0/W/B/lobes-of-brain.jpg

Functions of the LobesFrontal lobes: movement, decision making, problem solving, and planning.

Occipital lobes: involved with vision and color recognition.

Temporal lobe: hearing, emotional response, memory and speech.

Parietal lobe: receives and processes sensory information.

The Brain and Nervous SystemThe human brain is made of 100 to 200 billion neurons or nerve cells

Neurons are different from other body cells because they are not tightly packed together.

There are tiny gaps between neurons where fibers from different neurons come together but do not touch.

Chemicals released from neurons cross over and send messages to one another.

Neuron or nerve cell

Production of neurons is largely complete by the second trimester of pregnancy.

Once neurons are in place they differentiate by establishing their unique functions and by extending their fibers to form synaptic connections with neighboring cells.

Neural fibers and synapses grow at an astounding rate during the first two years.

Peak period of brain growth is also followed by ‘programmed cell death’.

Neurons or Nerve Cells

Stimulation of neurons is important for their survival.

Neurons seldom stimulated lose their synapses in a process called synaptic pruning.

Synaptic pruning returns neurons not needed to an uncommitted state to be used at a later stage of development.

Neurons and Synapses

Half the brain size is made of glial cells, which coat the neural fibers with fatty cells in a process called myelinization. Myelinization improves the efficiency of message transfer.

At birth the brain is 30% of adult size, at 2 years 70% and at 6 years 90%.

Neurons and Myelinization

The cerebral cortex has two hemispheres - left and right that differ in their functions

Each side receives information and controls the opposite side of the body.

Left hemisphere is largely responsible for verbal abilities and positive emotions

Right hemisphere is largely responsible for spatial abilities and negative emotions.

Lateralization and Plasticity

This specialization is called lateralization.

Left side deals with processing information in a sequential and analytical way. The right hemisphere for holistic, integrative manner.

A lateralized brain is more effective.

Brain plasticity is a process where when one part of the brain is damaged other parts take over its function. In a highly lateralized brain this may not be possible.

The younger the child when damage takes place the greater the chances of recovery.

Handedness; left or right develops as a result of lateralization.Left handedness is linked to less lateralization.

The cerebellum at the rear base of the brain, is responsible for aiding balance and control of body movement. This does not complete myelinization till 4 years of age.

The existence of sensitive periods in the development of cerebral cortex has been proven by studies on animals.

Surges in frontal lobe activity are also seen in human infants during different stages.

Between age 3 and 6 the frontal lobe areas for planning and organizing show increased activity.

Brain growth and Sensitive periods.

Massive production of synapses account for brain growth in the first 2 years.

Synaptic pruning, myelinization, and longer distance connections between other parts of the brain account for later ones.

Experience wires a child’s brain development but overstimulation is as harmful as under-stimulation.

Refers to control over actions that help infants/toddlers get around in the environment.

The ability of humans to use two legs and walk involves the whole body

Gross Motor Development

Fine motor development.Refers to development of small muscles and the ability to control use of the hands and feet, do activities that involve small muscles of the fingers, toes, and other parts of the body.

Small muscle development is necessary for physical activities such as grasping, cutting, throwing and drawing.

Reaching and Grasping

Newborns make poor coordinated swipes called pre-reaching.

The grasp reflex is replaced by the ulnar grasp.

By the end of the first year infants use the thumb and index finger in a well coordinated pincer grasp.

Bowel and Bladder Control

Urination and bowel movements are part of muscular development.

Children must consistently identify the signals from a full bladder or rectum and wait for the right place to open these muscles; then they are ready for toilet training.

Toilet Training

Other signs of toilet training readiness include;

A toddler who stays dry for several hours at a time.

Stops playing during urination or bowel movement.

Is bothered by wet or full diaper.

References

Berk, L.E. (2003). Child Development (5th Ed). USA: Pearson Education Inc.

Influences on Physical Growth

Heredity

Hormonal Influences: growth hormone deficiency.

In some societies there is a bias towards height or stature correlating it to competence and leadership

Influences on Physical GrowthBreastfeeding: helps myelinating the nervous system and enhances functioning of immune system.

Lack of protein can lead to Kwashiorkor, which usually strikes toddlers or Marasmus that strikes infants.

Iron deficiency or anemia leads to improper functioning of the central nervous system.

MARASMUS

The food pyramid

http://abcnews.go.com/Health/food-pyramid-food-plate/story?id=13743137#.T3_or-

2D76E

http://safe-to-be-slender.blogspot.com/2011/11/food-pyramid-is-now-food-plate-

method.html

Influences on Physical GrowthUnhealthy eating habits can lead to obesity (Stettler et al, 2005).

Lack of love and attention can lead to

a) Non-organic failure to thrive syndrome

b) Deprivation dwarfism.

Chronic childhood diseases can lead to stunted growth though most of the time children undergo catch up growth

Motor Skill Development

Growth in the ability to use the body and physical skills.

Processes by which we acquire movement patterns and skills.

Gross Motor Skill DevelopmentMovements such as walking, running, and catching that extend the large muscles of the body, arms and legs.

Early physical development experiences in the curriculum help children develop competences, interest in physical activities, provides release of tension and promotes relaxation.

Gross Motor Skill Development in child-careTo facilitate a child’s gross motor development provide various kinds of sturdy and durable equipment.

Equipments for lifting, pulling, and pushing around.

An unobstructed area for play.

Outdoor play & Gardening.

Gross motor skills provide kinesthetic awareness, flexibility, coordination and agility.

Gross motor development from 2-3 years

Walks more rhythmically, hurried walk turns to run.

Jumps, hops, throws, and catches with rigid upper body.

Pushes riding toy with feet, little steering.

From 3 to 4 years

Walking up stairs, alternating feet, and downstairs, leading with one foot.

Jumps and hops, flexing upper body.

Throws and catches with slight involvement of upper body, still catches by trapping ball against chest.

Pedals and steers tricycle.

From 4 to 5 years

Walks downstairs, alternating feet, runs more smoothly.

Gallops and skips with one foot.

Throws ball with increased body rotation and transfer of weight on feet, catches ball with hands.

Rides tricycles rapidly, steers smoothly.

From 5 to 6 years

Increasing running speed to 12 feet per second.

Gallops more smoothly, engages in true skipping and sideways stepping.

Displays mature, whole body throwing and catching patterns, increases throwing speed.

Rides bicycles with training wheels.

From 7 to 12 years

Increases running speed to more than 18 feet per second.

Displays continuous fluid skipping and sideways stepping.

Increases vertical jump from 4 to 12 inches and broad jump from 3 to over 5 feet, accurately jumps and hops from square to square.

Increases throwing and kicking accuracy, distance and speed.

Includes the whole body in batting a ball, batting increases in speed and accuracy.

Dribbling changes from awkward slapping of the ball to continuos, relaxed even stroking.

Growth Patterns.Large motor activities that make use of large muscles; develop first.

Large muscles develop before small muscles do.

Impressive array of large motor coordination emerges in the first 36 months.

There are individual differences in rates and sequence of development. Awareness of sequence is more helpful than the exact age particular traits emerge.

Small motor development develop from head down and from the central axis of the body outwards - cephalocaudal and proximodistal.

Vision and hearing develop first in infants.

Perceptual motor development i.e. relationship between a child’s perception and motor response, influences learning.

Growth pattern

Fine Motor Development in Child CarePlanning time to engage with a wide variety of play materials involving the small muscles; fingers, toes, and other parts of the body.

Examples are crafts, puzzles, threading, moulding, playing with blocks.

To ensure proper motor development, general health and nutritional needs should be met.

Ongoing assessment of physical and motor abilities should be done. For e.g. reflexive reactions, posture, balance, flexibility, voluntary movement, transitional movement, mobility preference patterns, eye-hand, hand-mouth and eye-foot coordination, chewing and swallowing efficiency.

Early intervention in the form of therapy, assessment, purposeful activity and inclusive environment should be provided.

Children with Special Rights

Relationship between physical/motor development and social and emotional development.

Each emerging motor skill contributes to the child’s emerging self concept and sense of self efficacy [feeling that one’s efforts are effective]

With the development of self help skills, children develop positive self image.

Body awareness and gender awareness comes with increased motor development. Toilet training is a part of this though it is a slow maturational process.

Relationship between physical/motor and cognitive developmentAs neurons develop in the brain their continued growth and survival depends on environmental stimulation.

The quantity and quality of stimulation has long term implications for cognitive development. Visual, olfactory, auditory, tactile, taste and kinesthetic stimulation enhance brain growth.

Opportunities for large and small muscle movement enhance sensory exploration.