Lifespan Development

Lifespan Development Module 4; Infancy

Module Learning Outcomes Describe human development during infancy • 4.1 Describe physical growth and development in infants and toddlers • 4.2 Explain cognitive development in infants and toddlers • 4.3 Explain emotional and social development during infancy

Physical Growth & Development in Infants

Learning Outcomes: Physical Growth & Development in Infants • 4.1Describe physical growth and development in infants and toddlers • 4.1.1: Summarize overall physical growth patterns during infancy • 4.1.2: Describe the growth of the brain during infancy • 4.1.3 Explain gross and fine motor skills in infants • 4.1.4 Explain newborn perceptual abilities • 4.1.5 Explain the merits of breastfeeding • 4.1.6 Discuss the importance of nutrition to early physical growth, including nutritional concerns for infants and toddlers such as marasmus and kwashiorkor • 4.1.7 Describe sleep concerns for infants • 4.1.8 Explain the vaccination debate and its consequences

Overall Physical Growth • Birth weight & length • Normal weight range ~ 5lb 8 oz to 8lb 13oz • Normal length range ~ 19.5 inches • Babies lose approx. 5% of body weight in first few days • Normal adjustment to life outside womb- waste elimination, feeding • Physical proportions • Head-to-body ratio: head comprises 25% of total length at birth • Percentiles: 1-100 • Failure to thrive: a child born in normal ranges falls below 20th percentile • Detection is key to medical intervention Photo credit: modification of work by Kerry Ceszyk

Physical growth, continued • Weight: • At 4 months old, weight typically doubles • At one year, weight has tripled • By age 2, weight has quadrupled. • Length: • Average length at 12 months ~28.5-30.5 inches • Average length at 24 months ~33.2-35.4 inches (CDC, 2010). Children experience rapid physical changes through infancy and early childhood.

Brain Growth- The First Two Years • Growth • Physical size of brain increases • At birth, brain is 25% adult weight • At 2-years-old, 75% • Neural development • Most neurons are present at birth, not fully developed • Transient exuberance: period of prolific dendritic connections • Myelination: myelin sheath (fatty cells) protects axons, speeds neural transmissions • Pruning: unused connections eliminated in favor of much-used connections • Prefrontal cortex • Least-developed portion of brain at birth; substantial growth During transient exuberance, a single neuron may have thousands of dendrites

Motor Development • Reflexes are inborn • Some are necessary for survival • Rooting reflex, breathing, sucking reflex • Some signify health, development • Moro reflex, stepping reflex, palmar grasp • Motor development is orderly • Follows cephalocaudal (head-down) proximodistal (center-out) principles • Gross Motor Skills • Large muscle groups • Fine Motor Skills • Small, coordinated muscle movements • Pinching, grasping This baby is working on his pincer grasp.

Motor & Sensory Development • Sensation & Perception • Sensation: interaction with sensory receptors • Perception: interpreting information sensed • Sensory Development • Sight- least developed at birth • Newborns see ~8-16 inches in front of them • Preference for faces, unusual, interesting, exciting images • Hearing: most developed at birth • In the womb, babies know the sound of mother’s voice • Touch/pain • Physiological reactions indicate sensation of pain- circumcision • Touch- necessary and comforting • Taste/smell • Ability to distinguish flavors: sweet, salty, sour, bitter (prefer sweet tastes) • Identify mother’s smell easily

Nutrition • Breastfeeding- “breast is best” • Colostrum: “liquid gold,” nutrient-dense, first days of life • Breastmilk has iron, fats, proteins, for proper development • Alternatives to breastfeeding • Formula feeding may be necessary in various conditions (mother doesn’t produce enough milk, adoptive or two-father family, mother has communicable disease, etc.) • Introducing solid foods • Start simple: one at a time is best, spaced days apart to ID allergies • Malnutrition & clean water access • Kwashiorkor: “displaced child’s disease”- lack of sufficient nutrition • Marasmus: starvation from lack of calories, protein • Milk anemia: Lack of iron from drinking cow’s milk in place of more nutritive foods • Clean water makes clean formula Breastmilk changes in composition with a newborn’s development and needs.

Sleep & Health • Infant sleep requirements • From 0-2 years, average 12.8 hrs/day • Newborns sleep 14-17 hrs • SIDS: many risk factors, many unknowns • Sudden Unexpected Infant Deaths (SUID): some identified causes • “Back to Sleep” • Back-sleeping recommended for every sleep • No soft bedding, blankets, potential hazards • Co-sleeping • Benefit of skin-to-skin contact • Risk of child suffocation, increased risk w/ parental drug/alcohol use • Sleep schedules • Nighttime waking is common • Many infants sleep 6 hrs during night by 6 months • Not doing so does not indicate a serious problem, but individual differences

Vaccinations • Immunizations: the debate • Personal beliefs, opt-out programs, religious beliefs • Need for community protection, prevent resurgence of diseases • Herd immunity • 90%+ of population is vaccinated, population is protected • Approx. 1 in 14 children isn’t vaccinated • Outbreaks • More frequent as fewer opt to vaccinate Children in communities throughout the world can benefit from immunizations and herd immunity.

Practice Question 1 Which nutrient found in breast milk is essential to myelination? • Calcium • Iron • Fat • Proteins

Class Activity: Vaccinations • Break into small groups to discuss vaccinations and public health. • What is your opinion on vaccinations? • Should they be mandatory? • Should individuals have the opt-out choice? • Write a resource paper, citing scholarly sources, supporting your arguments.

Cognitive Development in Infants & Toddlers

Learning Outcomes: Cognitive Development in Infants & Toddlers • 4.2 Explain cognitive development in infants and toddlers • 4.2.1 Describe each of Piaget's theories and stages of sensorimotor intelligence • 4.1.2: Describe the growth of the brain during infancy • 4.2.2 Explain learning and memory abilities in infants and toddlers • 4.2.3 Describe stages of language development during infancy • 4.2.4 Compare theories of language development in toddlers • 4.2.5 Explain the procedure, results, and implications of Hamlin and Wynn's research on moral reasoning in infants

Cognitive Development: Piaget & Sensorimotor Intelligence • Schemas: mental representations used to understand the world • Assimilation: modification of new information to fit into our existing schemas • Accommodation: reorganizing what we know to fit new information • Six stages of sensorimotor intelligence • Stage 1- Reflexes (Birth- 6 weeks) • Stage 2- Primary Circular Reactions (6 weeks- 4 mo.) • Stage 3- Secondary Circular Reactions (4-8 mo.) • Stage 4- Coordination of Secondary Circular Reactions (8-12 mo.) • Stage 5- Tertiary Circular Reactions (12-18 mo.) • Stage 6- Mental Representation (18-24 mo.) • Object Permanence • Knowledge something exists when out of sight (understanding ~8 mos/ mastery ~12-24 mos)

Learning & Memory Abilities in Infants • Piaget underestimated infant memory ability • Lacking in language to express memory • Experiments: preferential looking • Infantile amnesia • Infants and toddlers form memories, remember them weeks, months later • Lack of memory years later • Encoding/ retrieval failures • Older children, adults use linguistic retrieval methods • Misalignment between encoding and new memory organization

Language Development • Phonemesare basic units of speech, which make morphemes, the smallest meaningful units of speech • When a child starts vocalizing, they produce all phonemes • With specialization, only native phonemes are easy to reproduce • Stages of language development: • Stage 1: Reflexive Communication • Stage 2: Reflexive communication; interest in others • Stage 3: Intentional communication • Stage 4: First words • Stage 5: Simple sentences (two words) • Stage 6: Sentences of three or more words • Stage 7: Complex sentences; has conversations This 8-month old baby boy is likely babbling and gesturing to communicate

Language Development, cont. • Intentional vocalizations: gurgling, cooing, learn conversational cadences • Babbling, gesturing: syllable repetition, gesturing, sign language • Babies understand more language than they can produce • Holophrasic speech: partial words convey thoughts • People close to the child often interpret correctly • Underextension: a word may only be used for one specific think • Example: “Mommy” is my mother, so I shout for her in the grocery store when I am lost • Overextension is more common- generalizing • First words, cultural influences • Nouns, verbs, relationships- parts of speech vary by language & culture • Vocabulary growth spurt/ naming explosion: rapid vocabulary expansion • Many new words are nouns; child can name things around them & in the world • Two-word sentences, telegraphic speech: Lacks complete grammar, yet conveys meaning (like text messages) • Child-directed speech: captures children’s attention, articulates sounds

Theories of Language Development • Nativism- Noam Chomsky • Language Acquisition Device- innate ability to learn language, understand conventions and syntax • Children learn language through exposure, can learn any language • Critical periods- during these times learning is most important • Behaviorism- B.F. Skinner • Language is taught through reinforcement • Social Pragmatics- Tomasello & Hermann • Communication develops from need to communicate, join social world • All have components of truth and help explain language learning

Moral Reasoning in Infants • Kohllberg • Methodology relies on asking questions to determine moral justification • Infants & toddlers can’t communicate this with limited vocabulary • Hamlin & Wynn devised experiments to test babies’ morality • Hamlin & Wynn experiments: the bottom line • Children refer prosocial behavior • Prefer others like themselves • Do children have just world belief and revenge motives? How do we know what this little one is thinking? Perhaps preferential looking or reaching can lend insight into infant morality.

Practice Question 2 Why is the stage of rapid vocabulary growth in toddlerhood often called the “naming explosion?” • The child learns mostly people’s names in his/her expanding vocabulary. • Words the child adds to their repertoire are mostly nouns: people, places, and things. • Pronouns are an important part of vocabulary growth, as children learn how to properly refer to other people. • The child usually enters pre-school programs at this age and revels in reciting names of classmates.

Class Activity: Earliest memories • Childhood memories are ephemeral, but some have lasting impact. Think of your earliest childhood memory and try to describe it in as much detail as possible. • Note the retrieval cues you used and recall anything you can about your surroundings at the time the memory occurred. • Share your memories in small groups and discuss any commonalities between your earliest memories.

Emotional & Social Development During Infancy

Learning Outcomes: Emotional & Social Development During Infancy • 4.3 Explain emotional and social development during infancy • 4.3.1 Describe self-awareness, stranger wariness, and separation anxiety • 4.3.2 Contrast styles of attachment • 4.3.3 Describe temperament and the goodness-of-fit model • 4.3.4 Use Erikson’s theory to characterize psychosocial development during infancy

Emotional Development • Attraction & withdrawal • Social smiling- appears ~2 months, laughter at 3-5 months • Displeasure- frustration is normal, sadness can indicate withdrawal • Stranger wariness- appears ~6-15 months • Indicator of memory- familiar and unfamiliar • Separation anxiety • Shows cognitive development: “where has my caregiver gone?” • Peaks around 8-10 months, declines later w/ healthy attachment • Emotional regulation • Co-regulation: parents help manage amount of stimuli, soothe and comfort A parent may help this child regulate his/her emotions by soothing the child or removing extra stimulus.

Self-awareness • Self-awareness: “I, me, my, etc.” • Develops around 15-24 months • Understanding of self as an object • “Rouge test” or mirror test: does the baby touch their own nose or the mirror? • Rochat’s stages • Differentiation: self vs. non-self awareness (from birth) • Situation: Imitation, reaching for objects away from self (by 2 months) • Identification: Self-referential language, pass rogue test (by 2 years) • (Later stages:) • Permanence: One’s sense of self persists through time & space • Self-awareness/ meta-self-awareness: Third-person perspective

Attachment • Emotional needs vs. physical needs- Harlow’s monkey test • Comfort over sustenance • Ainsworth’s strange situation test- tested attachment styles w/ reactions • Four main types of attachment: • Secure(~65% of babies): parent serves as secure base of exploration • Insecure- avoidant: toddler reacts to parent like a stranger; unresponsive to parent, slow to show positive feelings • Insecure- resistant/ambivalent: clings to parent when they leave, reject affectionate attempts on caregiver return • Does not explore the new environment • Disorganized • Lease secure attachment; often unpredictable parental behavior, may be from abuse • Child has not learned emotional regulation from this model

Psychosocial Development • Temperament: Chess & Thomas- 9 dimensions • Activity level • Rhythmicity or Regularity • Approach-Withdrawal • Adaptability • Responsiveness • Reaction Intensity • Mood Quality • Distractibility • Persistence & Attention Span • From these dimensions, 4 main categories: • Easy babies (40%): overall positive disposition • Slow-to-warm (15%): relatively calm, slow to adapt, withdraw from new situations • difficult babies (10%): negative moods, slow to adapt to new situations • Undifferentiated (35%): combination/variety of dispositional factors • Goodness-of-fit model • Children’s adjustment largely depends on how well their environment is suited to meet their needs • Parenting/communication style matches

Erikson’s stages- Infants & Toddlers • Trust vs. mistrust • Resolution: Learning the world is a safe place • Unresolved: The world is an untrustworthy or dangerous place • Autonomy vs. shame & doubt • Resolution: Taking initiative and trying to do things one’s self is desirable • Unresolved: One’s autonomy is thwarted and discouraged. The child learns to doubt his or her instincts and feel shame at taking initiative Discovery and experimentation are vital parts of learning autonomy

Practice Question 3 Ainsworth’s “Strange Situation” test was designed to test what construct? • Self- awareness • Moral development • Object permanence • Attachment style

Practice Question 4 Which of the following statements regarding temperament is TRUE? • An undifferentiated temperament is fairly common, and means a child does not neatly fit into one category. • Undifferentiated temperament means a child’s temperament is disorganized and likely stems from abusive parental relationships. • An easy baby never displays negative emotion. • A slow-to-warm baby becomes an easy baby under the right conditions of nurturing and attachment.

Quick Review • What are Piaget's theories and stages of sensorimotor intelligence? • How does the brain grow during infancy? • What learning and memory abilities do infants and toddlers display? • How does language develop in stages during infancy? • What are the major theories of language development in toddlers, and how do they compare and contrast? • How did Hamlin and Wynn conduct their research on moral reasoning in infants, what were their results, and what did their research reveal? • What role do self-awareness, stranger wariness, and separation anxiety in infancy? • What styles of attachment did Ainsworth describe and test, and how do they compare? • How do a child’s temperament and the goodness-of-fit model for parenting relate? • How did Erikson characterize psychosocial development during infancy?

Quick Review - continued • What are Piaget's theories and stages of sensorimotor intelligence? • How does the brain grow during infancy? • What learning and memory abilities do infants and toddlers display? • How does language develop in stages during infancy? • What are the major theories of language development in toddlers, and how do they compare and contrast? • How did Hamlin and Wynn conduct their research on moral reasoning in infants, what were their results, and what did their research reveal? • What role do self-awareness, stranger wariness, and separation anxiety in infancy? • What styles of attachment did Ainsworth describe and test, and how do they compare? • How do a child’s temperament and the goodness-of-fit model for parenting relate? • How did Erikson characterize psychosocial development during infancy?

Lifespan Development