Child & Adolescent Psychology - Chapter 5: Infancy, Physical Development

cephalocaudal development

head to tail

brain is more important, so it is developed while legs are wobbly after birth

proximodistal development

in to out

• nervous system, heartbeat, respiration, digestion, waste elimination processes are closer to central axis and more important

• limbs are developed later

differentiation

specialization, increase in complexity

we start with basic structures and functions and become more complex

growth in infancy

lots of growth happens

• birth weight: 2x in 5 months, 3x in 12 months

• height: boys grow faster generally, increase by 50% in 12 months

failure to thrive

disorder of impaired growth in infancy and early childhood

characterized by failure to gain weight in normal growth patterns

• bad calorie intake can come from a variety of factors

  • lack of food

  • breastmilk issues

  • structure difficulties from cleft lip/palate

  • PPD

  • child neglect → attachment disorder

  • GERD

FTD organic

due to health problems and not environmental factors

mainly malabsorption/caloric retention deficiency

• marasmus

• kwashiorkor

marasmus

diet lacks essential nutrition → malnutrition/nourishment

kwashiorkor

lack of protein → body breaks down protein reserves → stomach enlargement, feet swelling

canalization

tendency of growth rates to return to normal after environment induced change

breastfeeding

pros

• cheaper

• attachment/bonding

• lower infant obesity, risk of breast/ovarian cancer in mother

• better neural/behavioral organization, bone strength

• shrinks uterus, helps mother lose weight after birth

• mother is less stressed due to oxytocin

• baby prefers it to formula

• colostrum

cons

• embarrassment/shame

• lack of maternal leave makes it hard to be the sole provider of substance

• can spread disease

• mother must be nourished herself

colostrum (breastfeeding)

the first milk, very good for child

• high in protein and carbs

• low in fat

• mother’s antibodies boosts the child’s immune system

nerve

bundle of axons from many neurons

neurogenesis

creation of neurons through mostly exercise/activity and other stimulation

neurons

cells that receive and transmit messages from the body, about 100 billion

• reflexes, perception, visual-motor coordination, cognition

dendrites

root-like part of the neuron, receive messages

axon

long, thin part of a neuron, sends messages via branching axon terminals

myelin sheath

fatty, white insulation around the axon, speeds up transmission

myelination

creation of myelin sheaths around the axon, quickest until 2 years

fast myelination thrives on exploration, movement, and use

• brain injuries, malnutrition, preterm births, lack of stimulation can slow rate of myelination

multiple sclerosis (MS)

immune system attacks myelin sheath, creating scar tissue on axons that slows neural transmission

causes pain and difficulty thinking + moving

pruning

use it or lose it

we lose that mental pathway for things we do not regularly use, our brains do not have endless capacity

neurotransmitters

chemical messengers that makes neural impulses possible, located within axon terminal in synapse spaces

medulla

brainstem part that controls basic autonomic function like breathing and the sleep-wake cycle

• involved with SIDs along with serotonin due to carbon dioxide regulation

cerebellum

hindbrain part, involved in muscle coordination, balance, and syncing movement to eyes and hands

cerebrum

forebrain’s 2 hemispheres that makes learning, thought, memory, and language, covered by the cerebral cortex

right hemisphere

connection

• facial recognition, visual imaging, voices, emotional responses

left hemisphere

problem solving

• speech, language comprehension (broca), logic (wernicke)

ulnar grasp

fingers grasp clumsily against palm

pincer grasp

use of opposing thumb to grasp objects between it and other fingers

locomotion

movement from one place to another

toddler

12 months to 30 months, between infancy and early childhood

toddles with short, uncertain steps

adolescence lasts until

25 years of age

sensation

stimulation of sensory organs to send info to the brain

perception

process that organizes sensations into a mental map of the world

visual accomodation

automatic focusing our eyes use

convergence

reduces double vision by inwardly moving the eyes to objects approaching

depth perception

tested via visual cliff and heart rate

• 1 month: no change, no awareness

• 2-3 months: lowers, curiosity

• 9 months: raises, fear due to depth perception being fully functional

perceptual constancy

tendency to perceive objects as the same even though the sensations produced by them may differ (ie: position or distance)

• size and shape constancy

size constancy

tendency to perceive that an object is the same size regardless of distance from your retina

shape constancy

tendency to perceive that an object is the same shape regardless of position viewed by your retina

infancy and hearing

pretty good, pitch range and sound localization improves

• before 6 months, english infants can discriminate languages, but at 10-12 months they cannot due to pruning

habituation

repeated stimulus → less attention to it

• do not tiptoe around an infant, they get used to it

nature and nurture and the nervous system

• nature: reflexes, sensory responses

• nurture: stimulation is required during critical periods to make voluntary motor activations possible