Psych: Chapter 4 - Infancy

What is failure to thrive?

A child born within normal growth ranges who later falls well below the norm on growth percentiles

Roughly what proportion of total body length does a newborn's head make up?

About a quarter of total body length — much more proportionally than in an adult

In what order does infant weight multiply relative to birth weight?

It roughly doubles by 4 months, triples by 1 year, and quadruples by age 2

What happens to the physical size of the brain during infancy?

It grows from about a quarter of adult weight at birth to about three-quarters of adult weight by age 2

What is transient exuberance?

A period of prolific dendritic connection growth in the infant brain

What is myelination?

The formation of a fatty myelin sheath around axons that protects them and speeds neural transmission

What is pruning, in brain development?

The elimination of unused neural connections in favor of frequently used ones

Which part of the brain is least developed at birth and undergoes substantial growth during infancy?

The prefrontal cortex

What is a reflex?

An inborn, automatic response

Which reflexes are necessary for survival?

The rooting reflex, breathing, and the sucking reflex

Which reflexes mainly signal health and development rather than survival?

The Moro reflex, stepping reflex, and palmar grasp

What two principles does motor development follow?

Cephalocaudal (head-down) and proximodistal (center-out)

What is the difference between gross and fine motor skills?

Gross motor skills use large muscle groups; fine motor skills involve small, coordinated movements like pinching or grasping

What is the difference between sensation and perception?

Sensation is the interaction with sensory receptors; perception is interpreting the sensed information

Which sense is least developed at birth?

Sight

Which sense is most developed at birth?

Hearing

What do newborns show a preference for visually?

Faces, and unusual, interesting, or exciting images

What tastes can newborns distinguish, and which do they prefer?

Sweet, salty, sour, and bitter; they prefer sweet tastes

What is colostrum?

The nutrient-dense first breastmilk produced in the first days of life, sometimes called "liquid gold"

What are some reasons formula feeding may be necessary?

The mother doesn't produce enough milk, an adoptive or two-father family, or a mother with a communicable disease

Why should solid foods be introduced one at a time, spaced apart?

To identify possible food allergies

What is kwashiorkor?

Malnutrition from a lack of sufficient nutrition, particularly protein, sometimes called "displaced child's disease"

What is marasmus?

Starvation resulting from a general lack of calories and protein

What is milk anemia?

A lack of iron that results from drinking cow's milk in place of more nutritive foods

What does "Back to Sleep" recommend?

Placing infants on their backs for every sleep, to reduce SIDS risk

What is a benefit and a risk of co-sleeping?

Benefit: skin-to-skin contact; risk: child suffocation, especially with parental drug or alcohol use

What does it mean if an infant is not yet sleeping through the night by a common milestone age?

It does not indicate a serious problem — it reflects normal individual differences

What is herd immunity?

Population-wide protection from disease once a high enough proportion of the population is vaccinated

What is a schema, in Piaget's theory?

A mental representation used to understand the world

What happens during Piaget's sensorimotor Stage 1 (Reflexes)?

Behavior is dominated by inborn reflexes

What happens during Piaget's sensorimotor Stage 2 (Primary Circular Reactions)?

The infant repeats simple actions centered on their own body

What happens during Piaget's sensorimotor Stage 3 (Secondary Circular Reactions)?

The infant repeats actions that produce interesting effects in the outside world

What happens during Piaget's sensorimotor Stage 4 (Coordination of Secondary Circular Reactions)?

The infant combines actions intentionally to reach a goal

What happens during Piaget's sensorimotor Stage 5 (Tertiary Circular Reactions)?

The infant actively experiments, trying new actions to see what happens

What happens during Piaget's sensorimotor Stage 6 (Mental Representation)?

The child can think about objects and actions mentally, without needing to physically try them

What is object permanence?

The understanding that something continues to exist even when it is out of sight

Why did Piaget underestimate infant memory ability?

Because infants lack the language to express what they remember

What is preferential looking?

A research method that studies infant memory and preference by observing what babies choose to look at longer

What is infantile amnesia?

The general lack of memory for one's own infancy later in life

Why does infantile amnesia likely occur?

Because of a mismatch between how memories were encoded before language developed and how memory is organized and retrieved using language later

What is a phoneme?

A basic unit of speech sound

What is a morpheme?

The smallest meaningful unit of speech

What phonemes can a child produce when they first start vocalizing, compared to later?

All possible phonemes at first; with specialization, only native-language phonemes remain easy to reproduce

What is holophrasic speech?

A single, partial word used by a child to convey a whole thought

What is underextension?

Using a word too narrowly, applying it to only one specific thing

What is overextension?

Using a word too broadly, generalizing it beyond its correct meaning

Which is more common, underextension or overextension?

Overextension

What is the vocabulary growth spurt (naming explosion)?

A period of rapid vocabulary expansion, with many new words being nouns

What is telegraphic speech?

Two-word sentences that lack complete grammar but still convey meaning

What is child-directed speech?

The exaggerated, simplified way adults naturally talk to babies, which captures attention and articulates sounds clearly

What does nativism (Chomsky) claim about language development?

That an innate Language Acquisition Device lets children learn language and understand its conventions and syntax

What does behaviorism (Skinner) claim about language development?

That language is taught through reinforcement

What does social pragmatics (Tomasello and Hermann) claim about language development?

That communication develops from the child's need to communicate and join the social world

How do the three theories of language development relate to each other?

All three have components of truth and together help explain language learning

Why couldn't Kohlberg's method be used to study infant moral reasoning?

Because it relies on asking questions, and infants and toddlers can't communicate with their limited vocabulary

What methods did Hamlin and Wynn use to study infant morality?

Preferential looking and reaching

What did Hamlin and Wynn find about infant moral preferences?

Infants prefer prosocial behavior and prefer others who are like themselves

When does social smiling typically appear?

Around 2 months

What is stranger wariness, and what does it indicate?

A wary or fearful reaction to unfamiliar people, indicating developing memory that can distinguish familiar from unfamiliar

What is separation anxiety, and what does it indicate?

Distress when a caregiver leaves, indicating cognitive development — the understanding that the caregiver has gone somewhere

What typically happens to separation anxiety with healthy attachment?

It declines over time

What is co-regulation?

Parents helping manage how much stimulation an infant is exposed to, soothing and comforting them

What is self-awareness, in the developmental sense?

Understanding oneself as a distinct object, expressed through words like "I," "me," and "my"

What is the rouge test (mirror test) used to measure?

Whether a child recognizes themselves in a mirror, based on whether they touch their own nose or the mirror's reflected mark

What is Rochat's "differentiation" stage of self-awareness?

Awareness of self versus non-self, present from birth

What is Rochat's "identification" stage of self-awareness?

Using self-referential language and passing the rouge test

What did Harlow's monkey experiments demonstrate about infant needs?

That infants seek comfort over sustenance — emotional needs matter as much as physical needs

What did Ainsworth's "strange situation" test measure?

Attachment style, based on a child's reactions to a caregiver leaving and returning

What characterizes secure attachment?

The parent serves as a secure base for exploration; the child is upset when the parent leaves and comforted when they return

What characterizes insecure-avoidant attachment?

The child reacts to the parent almost like a stranger, unresponsive and slow to show positive feelings

What characterizes insecure-resistant/ambivalent attachment?

The child clings to the parent when they leave but rejects affectionate attempts when the parent returns, and doesn't explore

What characterizes disorganized attachment?

The least secure style, often linked to unpredictable or abusive parental behavior, with the child lacking learned emotional regulation

What are the four broad temperament categories identified from Chess and Thomas's dimensions?

Easy, slow-to-warm, difficult, and undifferentiated

What is the goodness-of-fit model?

The idea that a child's adjustment depends on how well their environment, especially parenting style, matches their temperament

What is the task of Erikson's Trust vs. Mistrust stage?

The infant must learn that adults can be trusted and the world is a safe place

What is the task of Erikson's Autonomy vs. Shame and Doubt stage?

The toddler learns that taking initiative and trying things independently is desirable

What happens when autonomy is thwarted, in Erikson's theory?

The child learns to doubt their own instincts and feel shame at taking initiative