Child development E2

height and weight gains are greater

the first two years than any other time after birth

body fat develops quickly during

the first nine months, muscle development is slow and gradual

Cephalocaudal trend

head develops more rapidly than the lower part of the body

Proximodistal trend

growth that proceeds from the center of the body outward

skeletal age

a measure of bone development

skeletal age (girls vs.boys)

Girls are ahead of boys in physical maturity

skeletal age (African american)

African-American children tend to be ahead of EuropeanAmerican and Hispanic children

(brain) during the first two years,

neural fibers and synapses increase rapidly

Programmed cell death

an aspect of brain growth in which, as synapses form, many surrounding neurons die, making space for the synapses

(brain) neurons that are stimulated continue to establish

new synapses that support more complex abilities

(brain) stimulation initially results in

massive overabundance of synapses

Synaptic pruning

loss of synapses by seldom -stimulated neurons

Glial cells

responsible for myelination and can participate directly in neural communication

Myelination

the coating of neural fibers with myelin, an insulating fatty sheath that improves the efficiency of message transfer

Electroencephalogram (EEG)

Electrodes embedded in a head cap record electrical brain-wave activity on the cerebral cortex

Event-related potentials (ERPs)

Records frequency and amplitude of brain waves in response to stimuli

Functional magnetic resonance imagining (fMRI)

A magnetic scanner detects blood flow and oxygen metabolism in the brain

Positron emission tomography (PET)

Scanner emits X-rays that detect blood flow and oxygen metabolism

Near-infrared spectroscopy (NIRS)

Light is beamed at the brain and is absorbed by certain areas of cerebral cortex

Cerebral cortex

outermost layer of the brain, divided into four lobes (frontal,parietal, temporal, occipital)

frontal

most extended period of development

Prefrontal cortex

complex thought, consciousness, inhibition of impulses, selfregulation, memory

Lateralization

hemispheres develop specialized functions

left hemisphere

verbal abilities and positive emotions

right hemisphere

spatial abilities and negative emotions

Brain plasticity

enables other parts of the brain to take over functions of damaged areas

in the first few years

the brain is more plastic

Experience-expectant brain growth

ordinary experiences that influence the brain’s developing organization, occurs early and naturally

Experience-dependent brain growth

additional growth & refinement of established brain structures as a result of specific learning experiences, too early can overwhelm the brain’s neural circuitry

arousal patterns change due

to rapid brain growth

periods of sleep and wakefulness

become fewer and longer, increasingly conforms to night-day sleep-wake schedule

arousal patterns affected

by environment (cultural differences, sleep arrangements, bedtime routines)

(heredity) identical twins are much more alike in

body size than fraternal twin

(Heredity) when diet and health are adequate,

height and rate of physical growth depend largely on genetics

Catch-up growth:

a return to genetically determined growth path

nutrition

infants energy needs are 2x those of adults, breastfeeding/formula until 2 years, solid foods add 6 months.

breastfed and bottle fed infants do not differ

in quality of mother-infant relationship or later emotional adjustment, evidence on intelligence

marasmus

undernourishment causing an infants weight to be significantly low for their age

kwashiorkor

babies don’t get enough protein or other essential nutrients and too much fluid in the body tissues.

Habituation

gradual reduction in the strength of a response due to repetitive stimulation

Recovery

when a new stimulus/change in environment causes responsiveness to return to a high level

Novelty preference

assesses recent memory

Familiarity preference

assesses long term memory

(statistical learning) innate ability to extract frequently occuring patterns

from complex flow of information in environment, contributes to language acquisition

(statistical learning) helps explain the speed with which infants

sift through daily stimulation

infants are biased to attend to information that is

neither too simple nor too complex

Imitation

innate ability to learn by copying the behavior of another person (certain gestures, facial expressions)

Mirror Neurons

specialized cells in the cerebral cortex that underlie the ability to imitate by firing identically when hearing or seeing an action by another and when one carries out that action themselves

Gross-motor development

control over actions that help infant get around in the environment

Fine-motor development

control over smaller movements

Dynamic systems theory of motor development

mastery of motor skills involves acquiring increasingly complex systems of action

crawling>standing>stepping = walking

product of central nervous system development, movement capacities, goals, perceptual and cognitive, environmental supports

Prereaching

newborns make poorly coordinated swipes toward an object in front of them

Ulnar grasp

clumsy motion in which 3-4 month olds’ fingers close against the palm

Pincer grasp

infants use thumb and index finger to manipulate objects

sensation

5 senses

perception

children use their senses to gather and understand information and respond to the world around them

(hearing) newborns prefer to listen to speech over nonspeech sounds

and to their native tongue rather than a foreign language

(hearing) discrimination of speech sounds activates when

both auditory and motor areas in the cerebral cortex in young infants

(hearing) while listening, babies generate

internal motor plans that prepare them to produce the sounds they hear

(hearing) infants organize sounds

into increasingly complex patterns

once bilingual infants develop this sensitivity

they distinguish native sounds more rapidly and effectively

Perceptual narrowing effect

perceptual sensitivity that becomes increasingly attuned with age to information most often encountered

(hearing) infants capacity for statistical learning enables them

to detect speech regularities for which they will later learn meanings

(hearing) distinguishing word internal syllable from

word external syllable pair

depth perception

the ability to judge the distance of objects from one another and from ourselves

experience in crawling enhances depth perception

more crawling experience = more likely to avoid deep side of visual cliff

babies learn

to use depth cues for each body position separately

babies who have mastered sitting but are novice crawlers will

avoid a drop off in a sitting position, but crawl right over it

movement also promotes memory for

object location, hidden objects, and recognition of a previously viewed object from a new angle.

newborns prefer to look

at patterned rather than plain stimuli

(pattern perception) older infants can detect

familiar objects in incomplete drawings

(face perception) newborns prefer to look at

photos of faces with features arranged naturally

(face perception) the track face-like patterns movement

across their visual field farther than other stimuli

(face perception) tendency

to look at longer at attractive human faces

Size constancy

perception of an object’s size as the same, despite changes in the size of its retinal image

Shape constancy

perception of an object’s shape as stable, despite changes in the shape projected on the retina

Intermodal stimulation

simultaneous input from more than one sensory system

Intermodal perception

perception that combines information from more than one sensory system, resulting in an integrated whole

Amodal sensory properties

information that is not specific to a single modality but that overlaps 2+ sensory systems

intermodal sensitivity is crucial

for perceptual development

differentiation theory

infants actively search for invariant features of the environment

(differentiation theory) perceptual development as an innate tendency to

seek order and consistency that fine-tunes with age

Affordances

action possibilities that a situation offers an organism with certain motor capabilities

sensorimotor stage

piaget’s first stage, spanning the first two years of life

reflexive schemas

newborn reflexes

primary circular reactions

simple motor habits

secondary circular reactions

imitation of behaviors

coordination of secondary circular reactions

goal-directed behavior

tertiary circular reactions

testing an objects properties

mental representation

make believe play

Schemes

organized ways of making sense of experience

Adaptation

building schemes through direct interaction with the environment

Assimilation

using current schemes to interpret the external world

Accommodation

creating new schemes or adjusting old ones to better capture the environment

Organization

linking schemes with others to create a strongly interconnected cognitive system

Primary circular reactions

simple motor habits centered around the infant’s own body

Secondary circular reactions

imitation of familiar behaviors and interesting effects

Coordination of secondary circular reactions

intentional, or goal-directed, behavior

Tertiary circular reactions

exploring objects by acting on them in novel ways