(c) 2012 The McGraw-Hill Companies, Inc. Chapter 3 Physical and Cognitive Development in Infancy PowerPoints developed by Nicholas Greco IV, College of

(c) 2012 The McGraw-Hill Companies, Inc.

Chapter 3

Physical and Cognitive Development in Infancy

PowerPoints developed by Nicholas Greco IV, College

of Lake County, Grayslake, IL


Physical Growth and Development in Infancy

Head large relative to the rest of the bodyflops around uncontrollably

Infant becomes capable of sittingstandingstoopingclimbingusually walking


Cephalocaudal and Proximodistal Patterns

Cephalocaudal -- sequence in which the earliest growth always occurs at the top, beginning with the headphysical growth and differentiation of features

gradually works down from top to bottom Proximodistal -- sequence in which growth

starts at the center of the body and moves toward the extremitiesinfants control the muscles of their trunk and

arms before they control their hands


The First Year

Average North American newborn -- 20 inches long; 7½ pounds

Most newborns lose 5 to 7 percent of their body weight adjusting to feeding

They double their birth weight by the age of 4 months; nearly triple it by their first birthday

Infants grow about 1 inch per month during the first year


From Age 1 to 2 Years

At 2 years of age, children weigh approximately 26 to 32 poundsgaining a quarter to half a pound per monthattain about one-fifth of their adult weight

At 2 years, the average child is 32 to 35 inches tallnearly half of their eventual adult height


The Brain Cerebral cortex covers the forebrain like a

wrinkled cap Two halves, or hemispheres, based on

ridges and valleys in the cortex Four main areas, lobes, in each

hemispherefrontal lobes, occipital lobes, temporal lobes,

parietal lobes Lateralization -- specialization of function

in one hemisphere or the other



Neuron Parts of the neuron

Axon carries signals away from the cell body Dendrites carry signals toward itMyelin sheath -- a layer of fat cells -- provides

insulation and helps electrical signals travel faster down the axon

At the end of the axon are terminal buttons, which release chemicals called neurotransmitters into synapses

Synapses -- tiny gaps between neurons' fibers


Changes in Neurons Chemical interactions in synapses connect

axons and dendrites, allowing information to pass from neuron to neuron

The pace of myelination also varies in different areas of the brain

The infant’s brain is literally waiting for experiences to determine how connections are made



Changes in Regions of the Brain Both heredity and environment influence

synaptic overproduction and subsequent retraction

“Blooming (development) and pruning” vary considerably by brain region

Pruning -- unused connections are replaced by other pathways or disappear

Prefrontal cortex -- the area of the brain where higher-level thinking and self-regulation occur


Sleep

Considerable individual variation in how much infants sleep typical newborn sleeps 16 to 17 hours a daypreferred times and patterns of sleep also

vary Infants spend a greater amount of time in

REM (rapid eye movement) sleepby 3 months of age, the percentage of time in

REM sleep decreases


SIDS

Sudden infant death syndrome (SIDS) -- condition that occurs when infants stop breathing, usually during the night, and die suddenly without an apparent cause

SIDS is the highest cause of infant death in the United StatesRisk of SIDS is highest at 2 to 4 months of

age


Risk Factors for SIDS

SIDS decreases when infants sleep on their backs

More common in low birth weight infants Infants who are passively exposed to

cigarette smoke are at higher risk More frequent in infants who sleep in

soft bedding Less likely in infants who use a pacifier when

they go to sleep


Benefits of Breast Feeding Appropriate weight gain and lowered risk of

childhood obesity Fewer allergies Prevention or reduction of diarrhea,

respiratory infections, bacterial and urinary tract infections, and otitis media

Denser bones in childhood and adulthood Reduced childhood cancer and reduced

incidence of breast cancer in mothers and their female offspring

Lower incidence of SIDS


When Mother Should Not Breast Feed

If she is infected with AIDS or any other infectious disease that can be transmitted through her milk

If she has active tuberculosis If she is taking any drug that may not be

safe for the infant


Nutritional Needs

Nutritionists recommend that infants consume approximately 50 calories per day for each pound they weigh

This is more than twice an adult’s requirement per pound

Many U.S. parents are feeding their 4- to 24-month-old babies too few fruits and vegetables, and too much junk food


Dynamic Systems Theory Infants assemble motor skills for

perceiving and acting, which are coupled togetherWhen infants are motivated to do something,

they might create a new motor behaviorMastering a motor skill requires the infant’s

active efforts to coordinate several components of the skill

(Adolph et. al, 2010; Thelen & Smith, 2006)


Mastering a New Skill

The infant is motivated by a new challenge Partially accomplishes the task “Fine tunes” movements to make them

smoother and more effective “Tuning” is achieved through repeated

cycles of action and perception of the consequences of that action


Reflexes Reflexes -- built-in reactions to stimuli Genetically carried survival mechanisms

automatic involuntary

Allow infants to respond adaptively to their environment

Example reflexesRooting and sucking, Moro or startle reflex,

coughing, sneezing, blinking, shivering, and yawning


Infant Reflexes

INSERT FIGURE 3.7 HERE


Gross Motor Skills

Skills that involve large-muscle activitiesSitting with support -- 2 monthsSitting upright without support -- 6 to 7 months

of agePull themselves up and hold on to a chair -- 8

monthsStand alone – 10 to 12 months

With experience, babies learn to avoid risky situations, integrating perceptual information with the development of a new motor behavior



Gross Motor Development in the Second Year

Toddlers become more mobile 13–18 months

can pull a toy attached to a string use their hands and legs to climb up a number of

steps 18–24 months

toddlers can walk quickly or run stiffly walk backwards without losing their balance stand and kick a ball without falling and stand and

throw a ball jump in place


Fine Motor Skills

Finely tuned movements anything that requires finger dexterity

At birth, infants have very little control over fine motor skills

During the first two years of life, infants refine how they reach and graspPerceptual-motor coupling is necessary for

the infant to coordinate graspingExperience plays a role in reaching and

grasping


Sensory and Perceptual Development

Sensation occurs when information interacts with sensory receptors -- the eyes, ears, tongue, nostrils, and skin

Perception is the interpretation of what is sensed

Ecological View -- GibsonsOur perceptual system can select from the

rich information that the environment provides We directly perceive information that exists in

the world around us


Studying the Infant’s Perception

Perception brings us into contact with the environment in order to interact with and adapt to it

Visual Preference Method -- Infants look at different things for different lengths of time

Orienting response -- to determine if an infant can see or hear a stimulus

Habituation -- decreased responsiveness to a stimulus after repeated presentations of the stimulus

Dishabituation -- is the recovery of a habituated response after a change in stimulation



Visual Acuity and Color Newborn’s vision is estimated to be

20/600 on the well-known Snellan eye examination chart

By 6 months of age -- vision is 20/40 or better

By about the first birthday, the infant’s vision approximates that of an adult

By 8 weeks, possibly even by 4 weeks, infants can discriminate among some colors

(Banks & Salapatek, 1983; Aslin & Lathrop, 2008)


Perception of Pattern and Depth

Infants prefer to look at a normal human face rather than one with scrambled features

They prefer to look at a bull’s-eye target or black-and-white stripes rather than a plain circle

Depth perception -- visual cliffInfants develop the ability to use binocular

(two-eyed) cues to depth by about 3 to 4 months of age

(Gibson & Walk, 1960)


Hearing, Touch, and Pain Prenatally at 7 months, infants can hear

sounds such as mother’s voice and music Immediately after birth, infants cannot hear

soft sounds or pitch as well as adults do Newborns respond to touch and feel pain Infants also display amazing resiliency

Within several minutes after the circumcision surgery (which is performed without anesthesia), they can nurse and interact in a normal manner with their mothers


Smell and Taste

Newborns can differentiate among odors Sensitivity to taste might be present even

before birth At only 2 hours of age, babies made

different facial expressions when they tasted sweet, sour, and bitter solutions

At about 4 months of age, infants begin to prefer salty tastes, which as newborns they had found to be aversive

(Windle, 1940; Rosenstein & Oster, 1988; Harris, Thomas, & Booth, 1990)


Intermodal Perception

Involves integrating information from two or more sensory modalities, such as vision and hearing


Nature, Nurture, and Perceptual Development

Those who emphasize nature are nativistsThe ability to perceive the world in a competent,

organized way is inborn or innate

Those who emphasize learning and experience are called empiricists


Piaget’s Theory of Cognitive Development

Piaget thought we build mental structures that help us to adapt to the world

Adaptation involves adjusting to new environmental demands


Processes of Development

Developing brain creates schemes, which are actions or mental representations that organize knowledge

Assimilation -- children use their existing schemes to deal with new information or experiences

Accommodation -- children adjust their schemes to take new information and experiences into account

Organization -- is the grouping of isolated behaviors and thoughts into a higher-order system

(Lamb, Bornstein, & Teti, 2002)


Equilibrium and Disequilibrium

Cognitive conflict -- disequilibrium the child is constantly faced with inconsistencies and

counterexamples to existing schemes An internal search for equilibrium creates

motivation for change the child assimilates and accommodates, develops

new schemes, and organizes and reorganizes old and new schemes

Equilibration -- mechanism by which children shift from one stage of thought to the next

Cognition is qualitatively different in one stage compared with another


Sensorimotor Stage Infants construct an understanding of the world

by coordinating sensory experiences (such as seeing and hearing) with physical actions

Lasts from birth to 2 years At the end of this stage, 2-year-olds can produce

complex sensorimotor patterns and use primitive symbols


Object Permanence

Object permanence -- understanding that objects continue to exist even when they cannot be seen, heard, or touched

One of the infant’s most important accomplishments

Watch an infant’s reaction when an interesting object disappears. If the infant searches for the object, it is inferred that the baby knows it continues to exist


Evaluating and Modifying Piaget’s Sensorimotor

Stage The infant’s cognitive world is not as

neatly packaged as Piaget portrayed it Some of Piaget’s explanations for the

cause of change are debated Piaget's view of sensorimotor

development needs to be modified Some researchers conclude that infants’

perceptual abilities are highly developed very early in development


Evaluating and Modifying Piaget’s Sensorimotor

Stage A-not-B error is the term used to describe

the tendency of infants to reach where an object was located earlier rather than where the object was last hidden

The core knowledge approach states that infants are born with domain-specific innate knowledge systems


Learning, Remembering, and Conceptualizing

Infants can learn through operant conditioning Attention is the focusing of mental resources on

select information and improves cognitive processing on many tasks

Joint attention involves individuals focusing on the same object or event and involves:The ability to track another’s behaviorOne person directing another’s attentionReciprocal interaction



Meltzoff (2007) concludes that infants don’t blindly imitate everything they see and often make creative errors

He argues that beginning at birth there is an interplay between learning by observing and learning by doing

Critics say the newborns simply engage in automatic responses to a stimulus



Memory involves the retention of information over time

Some infants as young as 2 to 6 months can remember some experiences through 1½ to 2 years of age

Implicit memory refers to memory without conscious recollection

Explicit memory refers to conscious memory of facts and experiences

Infantile or childhood amnesia -- few memories before age 3


Concept Formation and Categorization

Concepts -- ideas about what categories representindispensable to competent cognitive

development Categories -- a way to group objects, events, and

characteristics on the basis of common properties By about 7 to 9 months of age, infants are able to

form conceptual categories rather than just making perceptual discriminations between different categories


Language Development

Language -- a form of communication—whether spoken, written, or signed—that is based on a system of symbols

All human languages have some common characteristicsRules describe the way the language works Infinite generativity -- the ability to produce an

endless number of meaningful sentences using a finite set of words and rules

(Berko Gleason, 2009)


Key Milestones in Language Development

Babies' sounds and gestures go through this sequence during the first yearCrying: can signal distress, but there are different

types of cries that signal different thingsCooing: about 1 to 2 months, gurgling sounds that

are made in the back of the throat and usually express pleasure during interaction with the caregiver

Babbling: In the middle of the first year, babies babble -- strings of consonant-vowel combinations, such as “ba, ba, ba, ba”

Gestures: Infants start using gestures, such as showing and pointing, at about 8 to 12 months of age


Recognizing Language Sounds

Phonemes -- the basic sound units of a language

First words occur between 10 to 15 months (average is 13 months)

Overextension -- the tendency to apply a word to objects that are inappropriate for the word’s meaning

Underextension -- the tendency to apply a word too narrowly


Two-Word Utterances Occurs by the time children are 18 to 24

months of age“Big car”“Where ball?”

Telegraphic speech is the use of short, precise words without grammatical markers such as articles, auxiliary verbs, and other connectives“Mommy give ice cream”


Biological Influences The ability to use language requires vocal

apparatus as well as nervous system capabilities

Brain regions predisposed for language Broca’s area -- an area in the left frontal lobe

of the brain involved in producing wordsWernicke’s area -- a region of the brain’s left

hemisphere involved in language comprehension

Aphasia -- a loss or impairment of language processing as a result of damage to brain



Biological Influences

Language Acquisition Device (LAD) -- Humans are biologically prewired to learn language at a certain time and in a certain way and to detect the various features and rules of language


Environmental Influences

Behaviorists opposed Chomsky's LAD hypothesisStated that language was nothing more than chains of

responses acquired through reinforcement

The behavioral view is no longer considered a viable explanation of how children acquire language

Language is not learned in a social vacuum Most children learn at a very early age


Environmental Influences

Vocabulary development is linked to the family’s socioeconomic status and the type of talk that parents direct to the child

Compared to professional parents, parents on welfare: Talked much less to young children Talked less about past events Provided less elaboration

Child-directed speech is language spoken in a higher pitch than normal, using simple words and sentences

Other strategies include recasting, expanding, labeling

Documents

(c) 2012 The McGraw-Hill Companies, Inc. Chapter 3 Physical and Cognitive Development in Infancy PowerPoints developed by Nicholas Greco IV, College of