Unit 2: Infant and Toddler Development Wendy DuCassé, MSW, LCSW * Power Point slides used with permission from Laura Berk

Unit 2: Infant and Toddler DevelopmentUnit 2: Infant and Toddler Development

Wendy DuCassé, MSW, LCSWWendy DuCassé, MSW, LCSW* Power Point slides used with permission from Laura Berk* Power Point slides used with permission from Laura Berk

Copyright © Allyn & Bacon 2008

Body GrowthBody Growth

Gain 50% in height from birth Gain 50% in height from birth

to age 1; 75% by age 2to age 1; 75% by age 2

Grow in spurtsGrow in spurts

Gain “baby fat” until about 9 Gain “baby fat” until about 9

months, then get slimmermonths, then get slimmer

Girls slightly shorter and Girls slightly shorter and

lighter than boyslighter than boys


Growth TrendsGrowth Trends

CephalocaudalCephalocaudal

““Head to Tail”Head to Tail”

Lower part of body Lower part of body grows later than the grows later than the headhead

ProximodistalProximodistal

““Near to far”Near to far”

Extremities grow Extremities grow later than head, later than head, chest, and trunkchest, and trunk


Epiphyses of the BoneEpiphyses of the Bone


The Skull at Birth The Skull at Birth


Neurons and Their Connective Neurons and Their Connective FibersFibers


Major Milestones ofMajor Milestones ofBrain DevelopmentBrain Development


Methods for Measuring Brain Methods for Measuring Brain Functioning Functioning


Regions of the Cerebral CortexRegions of the Cerebral Cortex


Lateralization and Plasticity of the Lateralization and Plasticity of the Cerebral CortexCerebral Cortex

The left and right hemispheres of the brain The left and right hemispheres of the brain control different functions. control different functions. Specialization of the two hemispheres is called Specialization of the two hemispheres is called lateralization. lateralization. – Left hemisphere: best at processing information in a Left hemisphere: best at processing information in a

sequential, analytic way. sequential, analytic way. – Right hemisphere: best at processing information in a Right hemisphere: best at processing information in a

holistic, integrative manner. holistic, integrative manner.

In a highly In a highly plastic plastic cerebral cortex, many areas cerebral cortex, many areas are not yet committed to one function, are not yet committed to one function, consequently, the cortex has a high capacity for consequently, the cortex has a high capacity for learning. learning.


Brain Plasticity Insights Brain Plasticity Insights

In children with injuries to the cerebral cortex that In children with injuries to the cerebral cortex that occurred before birth or in the first 6 months of life, occurred before birth or in the first 6 months of life, language delays persisted to about 3language delays persisted to about 3½ years of age. ½ years of age. Yet, by age 5, the children caught up in grammatical and Yet, by age 5, the children caught up in grammatical and vocabulary skills, showing that the undamaged area of vocabulary skills, showing that the undamaged area of the brain—either hemisphere—had taken over the the brain—either hemisphere—had taken over the language function. language function. Spatial skills showed more impairment after a brain Spatial skills showed more impairment after a brain injury. Researchers speculate that spatial processing is injury. Researchers speculate that spatial processing is more lateralized at birth. more lateralized at birth. Brain plasticity can occur later in adulthood, for example, Brain plasticity can occur later in adulthood, for example, in stroke victims.in stroke victims.


Sensitive Periods in Brain Sensitive Periods in Brain Development Development

Early, extreme sensory deprivation results Early, extreme sensory deprivation results in permanent brain damage and loss of in permanent brain damage and loss of function. function.

Babies born with cataracts in both eyes Babies born with cataracts in both eyes who have corrective surgery within 4 to 6 who have corrective surgery within 4 to 6 months show rapid improvement in vision.months show rapid improvement in vision.

The longer the surgery is postponed, the The longer the surgery is postponed, the less complete the recovery of visual skills. less complete the recovery of visual skills.


Brain Development in Orphanage Brain Development in Orphanage ChildrenChildren

Children adopted from Romanian orphanages Children adopted from Romanian orphanages before 6 months of age showed dramatic before 6 months of age showed dramatic cognitive and physical gains. cognitive and physical gains.

Those adopted after 6 months, however, Those adopted after 6 months, however, showed serious intellectual deficits. showed serious intellectual deficits.

The chronic stress of early, deprived orphanage The chronic stress of early, deprived orphanage rearing disrupts the brain’s ability to manage rearing disrupts the brain’s ability to manage stress, with long-term consequences. stress, with long-term consequences.


Relationship of Age at Adoption to Relationship of Age at Adoption to Mental Test ScoresMental Test Scores


Sensitive Periods in Sensitive Periods in Brain DevelopmentBrain Development

Experience-expectant Experience-expectant growthgrowth– Ordinary experiences Ordinary experiences

““expected” by brain to grow expected” by brain to grow normallynormally

Experience-dependent Experience-dependent growthgrowth– Specific experience, varies Specific experience, varies

widelywidely


Appropriate StimulationAppropriate Stimulation

Experience-expectant brain development Experience-expectant brain development takes place early and naturally as part of a takes place early and naturally as part of a preschooler’s daily routine. preschooler’s daily routine.

No evidence exists to support a sensitive No evidence exists to support a sensitive period in early life when mastering skills period in early life when mastering skills that depend on extensive training can that depend on extensive training can occur. In fact, rushing early learning can occur. In fact, rushing early learning can overwhelm young brains. overwhelm young brains.


Sleep PatternsSleep Patterns

Sleep moves to an adult-Sleep moves to an adult-like night-day schedule like night-day schedule during the first year.during the first year.Sleep needs decline from Sleep needs decline from 18 to 12 hours a day by 18 to 12 hours a day by age 2.age 2.Night wakings often Night wakings often increase between the increase between the ages of 1ages of 1½ and 2 years, ½ and 2 years, and then decline. and then decline.


Cultural Variations in Infant Cultural Variations in Infant Sleeping ArrangementsSleeping Arrangements

Cosleeping is the norm for 90% of the Cosleeping is the norm for 90% of the world’s population. world’s population.

Cultural values of collectivism versus Cultural values of collectivism versus individualism strongly influence infant individualism strongly influence infant sleeping arrangements. sleeping arrangements.

Cosleeping is increasing in North America, Cosleeping is increasing in North America, perhaps because more mothers are perhaps because more mothers are breastfeeding. breastfeeding.


Influences on Early GrowthInfluences on Early Growth

HeredityHeredity

NutritionNutrition– Breast v. Bottle FeedingBreast v. Bottle Feeding– MalnutritionMalnutrition

Emotional Well-BeingEmotional Well-Being– Problems Can Cause Problems Can Cause

Failure to ThriveFailure to Thrive


Benefits of BreastfeedingBenefits of Breastfeeding

Correct fat-protein balanceCorrect fat-protein balance

Nutritionally completeNutritionally complete

More digestibleMore digestible

Better growthBetter growth

Disease protectionDisease protection

Better jaw and tooth developmentBetter jaw and tooth development

Easier transition to solid foodEasier transition to solid food


Are Chubby Babies At Risk for Are Chubby Babies At Risk for Later Obesity? Later Obesity?

Recent research shows that there is a Recent research shows that there is a relationship between rapid weight gain in relationship between rapid weight gain in infancy and later obesity. infancy and later obesity. What to do?What to do?– Breastfeed for six months. Breastfeed for six months. – Avoid foods loaded with sugar, salt, and Avoid foods loaded with sugar, salt, and

saturated fats. saturated fats. – Promote physical exercise. Promote physical exercise. – Limit TV viewing time. Limit TV viewing time.


MalnutritionMalnutrition

TypesTypes

MarasmusMarasmus

KwashiorkorKwashiorkor

Iron-deficiency anemiaIron-deficiency anemia

Food insecurityFood insecurity

ConsequencesConsequences

Physical symptomsPhysical symptoms

Growth and weight problemsGrowth and weight problems

Poor motor developmentPoor motor development

Learning, attention problemsLearning, attention problems

Passivity, irritability, anxietyPassivity, irritability, anxiety


Nonorganic Failure to Thrive Nonorganic Failure to Thrive

The baby is offered enough food and has no The baby is offered enough food and has no serious illness, but still has a wasted body and is serious illness, but still has a wasted body and is withdrawn and apathetic. withdrawn and apathetic. Family circumstances surrounding failure to Family circumstances surrounding failure to thrive often help explain the problem. thrive often help explain the problem. When treated early, by helping the parents or When treated early, by helping the parents or placing the baby in a caring foster home, failure-placing the baby in a caring foster home, failure-to-thrive infants show quick catch-up growth. to-thrive infants show quick catch-up growth. Left untreated, most will remain small and have Left untreated, most will remain small and have lasting difficulties. lasting difficulties.


The Steps of The Steps of Classical ConditioningClassical Conditioning


Operant Conditioning TermsOperant Conditioning Terms

ReinforcerReinforcerIncreasesIncreases probability of probability of behavior occurring behavior occurring againagainPresenting desirable Presenting desirable stimulusstimulusRemoving unpleasant Removing unpleasant stimulusstimulus

PunishmentPunishmentReducesReduces probability probability of behavior of behavior occurring againoccurring again

Presenting Presenting unpleasant stimulusunpleasant stimulus

Removing desirable Removing desirable stimulusstimulus


Using Habituation Using Habituation to Study Infantsto Study Infants


Imitation Imitation

Imitation is a powerful method of learning. Imitation is a powerful method of learning. It is more difficult to induce in babies 2 to 3 It is more difficult to induce in babies 2 to 3 months old than right after birth.months old than right after birth.Andrew Meltzoff: newborns imitate as much as Andrew Meltzoff: newborns imitate as much as older children and adults do. older children and adults do. Mirror neurons enable us to observe another Mirror neurons enable us to observe another person’s behavior while simulating that behavior person’s behavior while simulating that behavior in our own brain.in our own brain.Meltzoff’s theory of newborn imitation as a Meltzoff’s theory of newborn imitation as a voluntary capacity is controversial. voluntary capacity is controversial.


The Sequence of Motor The Sequence of Motor Development Development

Gross motor Gross motor developmentdevelopment– crawling, standing, crawling, standing,

walkingwalking

Fine motor Fine motor developmentdevelopment– reaching and grasping reaching and grasping


Gross and Motor Development in Gross and Motor Development in the First Two Yearsthe First Two Years


Motor Skills as Motor Skills as Dynamic SystemsDynamic Systems

Increasingly complex Increasingly complex systemssystems of action with of action with each skilleach skill

4 factors in each new 4 factors in each new skill:skill:1.1. CNS developmentCNS development

2.2. Body’s movement capacityBody’s movement capacity

3.3. Child’s goalsChild’s goals

4.4. Environmental supportsEnvironmental supports


Steps in Steps in Reaching and GraspingReaching and Grasping

PrereachingPrereachingReachingReaching– With two hands, then oneWith two hands, then one

Ulnar GraspUlnar Grasp– Adjust grip to objectAdjust grip to object– Move objects from Move objects from

hand to handhand to hand

Pincer GraspPincer Grasp


Keeping Infants Keeping Infants and Toddlers Safeand Toddlers Safe

Provide safe toys Provide safe toys

Child-proof all rooms Child-proof all rooms

Continuously monitor the infant or toddler Continuously monitor the infant or toddler

Use a car seat, following government Use a car seat, following government regulations regulations

Report any unsafe toys and equipment Report any unsafe toys and equipment


Bowel and Bladder Control Bowel and Bladder Control

Toilet training is best Toilet training is best delayed until the months delayed until the months following the second following the second birthday. birthday.

Effective training Effective training techniques include:techniques include:– establishing regular establishing regular

toileting routines toileting routines – using gentle using gentle

encouragement encouragement – praising children for their praising children for their

effort effort


Developments in HearingDevelopments in Hearing

4 4 –– 7 months 7 monthsSense of musical phrasingSense of musical phrasing

6- 8 months6- 8 months““Screen out” sounds from non-Screen out” sounds from non-native languagesnative languages

7 7 –– 9 months 9 monthsDivide the speech stream into Divide the speech stream into word-like units word-like units

10 months10 monthsCan detect words that start with Can detect words that start with weak syllablesweak syllables


Improvements in VisionImprovements in Vision

Brain development helps infants reach adult levels Brain development helps infants reach adult levels of vision skills:of vision skills:2–4 months: focus and color vision 2–4 months: focus and color vision 6 months: acuity, scanning & tracking6 months: acuity, scanning & tracking6–7 months: depth perception6–7 months: depth perception


Steps in Depth PerceptionSteps in Depth Perception

Birth – 1 Birth – 1 month month Sensitivity to motion cues.Sensitivity to motion cues.

2 – 3 2 – 3 monthsmonths Sensitivity to binocular cues.Sensitivity to binocular cues.

6 –7 6 –7 monthsmonths

Sensitivity to pictorial cues. Sensitivity to pictorial cues.

Wariness of heights.Wariness of heights.


Steps in Pattern PerceptionSteps in Pattern Perception

3 weeks 3 weeks Poor contrast sensitivity.Poor contrast sensitivity.

Prefer large simple patterns.Prefer large simple patterns.

2 months2 monthsCan detect fine-grained detail. Can detect fine-grained detail. Prefer complex patterns.Prefer complex patterns.

4 months4 monthsCan detect patterns even if Can detect patterns even if boundaries are not really present.boundaries are not really present.

12 months12 monthsCan detect objects if two-thirds of Can detect objects if two-thirds of drawing is missing.drawing is missing.


Appearance of Checkerboards to Appearance of Checkerboards to Very Young Infants Very Young Infants


Subjective Boundaries Subjective Boundaries in Visual Patternsin Visual Patterns


Stimuli for Stimuli for Studying Studying

Infants’ Facial Infants’ Facial PerceptionPerception


Testing Infants’ Ability to Testing Infants’ Ability to Perceive Object Unity Perceive Object Unity


Differentiation Theory Differentiation Theory of Infant Perceptionof Infant Perception

Infants actively search for Infants actively search for invariantinvariant, unchanging , unchanging features of the environment.features of the environment.– Borders of stimuli, facesBorders of stimuli, faces

They note stable relationships between features.They note stable relationships between features.– Complex visual patterns, Complex visual patterns, intermodalintermodal relationships relationships

Perception gets more and more sensitive— Perception gets more and more sensitive— differentiationdifferentiation

Acting on the environment helps this process— Acting on the environment helps this process— affordancesaffordances

Documents

Unit 2: Infant and Toddler Development Wendy DuCassé, MSW, LCSW * Power Point slides used with permission from Laura Berk