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THE TOOLS THAT BABIES COME EQUIPPED WITH Reflexes in the Newborn

THE TOOLS THAT BABIES COME EQUIPPED WITH Reflexes in the Newborn

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Page 1: THE TOOLS THAT BABIES COME EQUIPPED WITH Reflexes in the Newborn

THE TOOLS THAT BABIES COME EQUIPPED WITH

Reflexes in the Newborn

Page 2: THE TOOLS THAT BABIES COME EQUIPPED WITH Reflexes in the Newborn

Early human reflexes

There are 27 major innate reflexesControlled by lower brain centersPlay an important part in stimulating early

development of CNS and musclesPrimitive reflexes—e.g., sucking, rooting for

nipple, Moro reflex, grasping—related to need for survival and protection

Postural reflexes—reactions to changes in position/balance—e.t., parachute reflex

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When reflexes disappear

Most early reflexes disappear in 6 months to a year after birth.

Protective reflexes (sneezing, blinking, yawning, shivering, pupillary reflex) remain.

Disappearance of unneeded reflexes on schedule is a sign that motor pathways in cortex have been partially myelinated, enabling a shift to voluntary behavior.

Doctors assess neurological function by seeing if reflexes disappear when they’re supposed to.

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Rooting Reflex (above pic)

Newborn Babinski reflex on right; normal non-newborn response on left

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Sucking reflex

Two purposes—babies get nourishment, and they get enjoyment out of sucking

Even fetuses show sucking reflexNon-nutritive sucking—85% of babies do it

(suck on pacifier, fist, etc.)As many as 40% of children suck their

thumbs after they’ve started school.Sucking behavior is also used to gauge a

baby’s attention or interest in people, things, or noises.

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The Sucking Reflex (this will often immediately follow the rooting reflex as baby searches for something to suck on)

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Smiling

Helps ensure an infant’s survival by making the adult feel tenderness toward him/her.

Two types of smiling—reflexive & social.Reflexive smiling—first month of life; child

smiles for no apparent reason, usually during sleep (doesn’t appear in alert state)

Social smiling—appears somewhere around 2 months of age (some say as early as 3 weeks); baby smiles in response to a face

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Reflexive smiling…4 days old

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Social Smiling: Zach 8 weeks

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“SLEEPING LIKE A BABY…”IS IT ALL IT’S CRACKED UP TO BE?

Sleep

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States of Arousal in Newborns

Regular sleep—8 to 9 hoursIrregular sleep—8-9 hoursDrowsiness—variesQuiet alertness—2 to 3 hoursWaking activity and crying—1 to 4 hours**Quiet alertness is the most variable and

fleeting. Time spent in each state depends on temperament.

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REM sleep in infants

Infants spend 50% of total sleep time in REM sleep

By age 3-5 years, it declines to 20%…the same amount an adult has

It’s thought that REM sleep is vital to baby’s development—helps stimulate the CNS.

REM sleep is disturbed in infants who are brain-damaged or have severe birth trauma.

Poorly sleeping babies are likely to be behaviorally disorganized & have problems learning. Trouble with interactional synchrony

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Where should baby sleep?

Attachment parenting proponents insist baby should sleep in “family bed” until h/she decides to sleep in own bed.

Called “co-sleeping”Opponents believe child should learn to fall

asleep in own bed; baby must be taught to put self to sleep

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Problems with the family bed

Increased sleep disorders in children (sleep problems found in 35-50% of co-sleepers), compared to 7-15% of those who sleep alone

Dental problems—co-sleeping babies continually feed during the night, which causes cavities

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Problems…cont.

Developmental problems—Controversial topic; some theorists believe that child can’t develop independent sense of self when co-sleeping

Peer problems—school-age cosleeping child could be made fun of

Marital problems—cosleeping creates difficulties for parents attempting intimacy

Safety problems—the biggest issue; sharing bed greatly increases chances of child dying during night (by smothering)

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SIDS—Sudden Infant Death Syndrome

Leading cause of death in US of infants between ages of 1 month and 1 year (2-3 per 1000 children die of SIDS in US every year)

SIDS especially prevalent in Australia & New Zealand; low in Japan and Sweden. Reasons unknown.

With SIDS, babies simply stop breathing during naps or nighttime sleep, and they die.

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Risk factors for SIDS

More common in winter when babies suffer more respiratory infections

More common in males than femalesHighest rates with babies 2-4 months of agePutting a baby to sleep on stomach is a big

risk factor—PUT BABY TO SLEEP ON ITS BACK!

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More risk factors for SIDS

Babies who have history of apnea—brief periods when breathing stops—are more likely to die of SIDS

Racial differences: SIDS rates highest in Native Americans, then Blacks, then Whites, and finally, Asians.

SIDS rates are higher among the poor and among moms who didn’t get proper prenatal care.

Preterm or low-birth-weight babies are at higher risk, as are those who had low APGAR scores.

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Smoking and SIDS

If women stopped smoking while pregnant, the SIDS rate would drop by 30%.

Babies who are exposed to smoke either prenatally or after birth (in the home) are 4 times more likely to die of SIDS.

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Brain differences in SIDS babies

Brains of SIDS babies often show signs of delayed maturation.

Myelinization of neurons has progressed at a slower rate

May be that inadequate fat intake in last month of pregnancy or during infancy may contribute to the problem (link with dietary fat)

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Pacifier use and SIDS

American Academy of Pediatrics issued a statement in October of 2005 advocating the use of pacifiers as a deterrent of SIDS.

Pacifier use has now been added to the SIDS prevention list.

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Another SIDS hypothesis

Between 2-4 months, reflexes decline and are replaced by learned, voluntary responses.

Respiratory & muscular weaknesses may prevent some babies from acquiring voluntary behaviors that replace defensive reflexes.

Instead of waking up or shifting position, they simply give in to death.

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Summary: Reducing risk factors

Do not smoke or allow baby to be exposed to any smoke.

Put baby on back to sleep.Keep room fairly cool (68-72 degrees).Don’t put blankets, stuffed animals, or

pillows in crib. Make sure mattress is firm.Eat well during pregnancy; don’t skimp on

fat.

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Sleep Problems in Infants

Nighttime waking is the most common problem.20-30% have a hard time going to sleep at night

and have nighttime waking problems. Infant waking at 1 year predict sleep problems at 4

years and are consistently linked to parents interacting with their babies at night (e.g., going in to comfort them when they hear them wake up).

Solution—”sleep train” your child, starting around age 4 months. Let them cry it out (within reason). Known as the Ferber method.

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YOU’LL WANT TO CRY RIGHT ALONG WITH THE INFANT.

Crying and Colic

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Crying

First way babies communicate with parents—signals distress

Usually cry because of physical needs, but they also cry when they hear other babies crying.

80-90% of babies have crying spells of up to 1 hour per day that aren’t easily explained.

Crying time often corresponds with dinnertime and may be related to sensory overload.

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Colic

A period of sustained, uncontrollable crying that differs from normal crying.

Crying must last for 2-3 hours at a time on a daily/almost-daily basis for at least 3 weeks to be considered colic.

Usually begins during the 2nd or 3rd week of life and lasts until about 3 months

Baby with colic is inconsolable and appears to be in pain. Acts hungry but can’t or won’t eat.

Eating and sleeping are upset by colic.

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Zach after 4 hours of crying

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Rejected Causes of Colic

Babies cry to exercise their lungsThey cry because of gastric discomfort

triggered by food allergies or sensitivityThey cry because of parental inexperienceColic is hereditaryColic is more common in babies whose

mothers had difficult pregnancies or deliveries

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Possible theories still being debated

Crying is a normal manifestation of a baby’s physiological immaturity, and colic is just an extreme form of it.

Immature digestive tract may contract violently when gas is passed, causing pain.

Painful intestinal spasms occur because of progesterone withdrawal as maternal hormones in baby’s body drop off.

Immature nervous system hasn’t yet learned to inhibit unwanted behavior (crying).

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Most plausible theory

Babies with colic lack a “calming reflex” that other babies are born with.

Can’t shut out sensory experiences.During first month (when colic is relatively

rare), newborns have a built-in blocking mechanism that allows them to shut out stimuli. Around the 1 month mark, the mechanism disappears, and they may have a hard time adjusting to the new sensations of life.

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5-step colic cure (“Cuddle Cure”—Harvey Karp)

Swaddle baby tightly so he can’t move.Put baby on side or stomachShush baby (make loud hushing sounds in

baby’s ear, preferably in rhythmic fashion)Swing baby from side to sideGive baby something to suck on—finger or

pacifierThese tips are known as the 5 S’s of the

Cuddle Cure. From The Happiest Baby on the Block by

Harvey Karp.

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IT MAY BE NATURAL, BUT IT’S NOT AS EASY AS YOU THINK.

Feeding the Baby

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Feeding the baby

Breast milk has been the standard for all of human history.

With the advent of formula, breast-feeding declined from the 1940s to 1970s, when over 75% of American children were formula-fed.

Today, about 2/3 of American women leave the hospital breastfeeding, but the figure drops to 30% still breast-feeding 6 months later.

Breast-feeding is more common in higher SES.

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Advantages of breast milk

Contains at least 100 ingredients not found in formula.

Composition of breast milk changes throughout the day to meet baby’s specific needs; also changes as baby matures

More easily digested than formula; baby has less stomach upset.

Has correct balance of sodium, fat, and protein to put less strain on baby’s kidneys

Baby absorbs calcium better with breast milk.

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Advantages cont.

Less risk of allergy to breast milk than to formula, although baby can be sensitive to something Mom has eaten.

Constipation almost never occurs in the baby who is breastfed.

Babies get essential antibodies that will bolster immune system. Get sick less often.

Breastfeeding may prevent obesity in children and adults.

Breast milk is free, convenient, and offers Mom some protection against breast cancer before menopause.

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Do moms who breastfeed lose weight faster?Mothers who breastfeed must take in an

extra 500 calories a day to compensate for calories lost during breastfeeding.

Theoretically, breastfeeding Moms should lose weight faster, and it’s always been said to be true.

New research suggests that breastfeeding moms lose LESS weight initially than bottle-feeding moms do, but 8 years later, they are thinner than their bottle-feeding counterparts.

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Is breastfeeding a form of birth control?

Often women who breast-feed don’t ovulate (and thus do not have a period).

Some women use breastfeeding as birth control, but this is unreliable.

You MAY ovulate while breastfeeding and could get pregnant without meaning to.

Breast-feeding moms can take a “mini-pill,” which is a specific version of birth control pills. It’s progestin-only, which won’t harm the baby.

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So why would anyone bottle-feed?

Breast-feeding is hard work and has some disadvantages to the mother.

It’s not easy to learn to breastfeed. It can be painful, too.

Nursing moms often have to nurse “around the clock.” Baby eats every 1 ½ hours or so instead of every 3-4 hours like formula-fed babies do.

Mom is solely responsible for feeding—can’t get help from others unless she pumps.

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More deterrents to breastfeeding

Mother must watch her diet and medication use just as she did while pregnant. Less freedom for her.

It’s draining and exhausting, which can lead to postpartum depression.

Interferes with sex in several ways: 1) no sex drive; 2) no vaginal lubrication; 3) breasts leak milk during sex

Nipples can become sore and cracked. Mom runs danger of developing mastitis.

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Advantages of formula

Baby isn’t hungry as often; can go longer between feedings

Other people can feed the baby, leaving Mom free to do other things.

You can gauge exactly how much baby eats and don’t have to worry about whether he’s getting enough.

No dietary or medication restrictions; no sexual interference.

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Are there IQ differences?

Some studies cite a difference of 7 IQ points between bottle-fed and breastfed children (breastfed children having higher IQ)

At least 3 longitudinal studies since 1999 have disputed this finding and have found no differences in intelligence, emotional stability, or attachment to the mother between breastfed and bottle-fed children.

It’s hard to say conclusively without experimental studies.

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Bottom line

Breast milk is clearly better for the baby, and the baby likes the taste of breast milk better, too.

Breast-feeding is not easier for the mom.If you choose to feed the baby formula,

h/she will still be getting excellent nutrition and won’t suffer any damage.

Feeding is NOT the primary ingredient to having a happy, healthy baby.

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Starting solids

Pediatricians recommend starting solids (“baby food”) between ages of 4-6 months, depending on baby’s weight and how easily he can swallow food.

Whether you start with fruits or vegetables is a matter of debate. Start one food and wait for 2-3 days to see if baby has an allergic reaction. Also introduce cereal.

Add meats last.

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Starting solids takes some getting used to. Some babies don’t like it. This is Drew’s first bite of solid food (rice cereal) at age 4 months.

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Obesity in infancy

New studies are focusing on the dangers of obesity in infancy because, contrary to what was thought only a few years ago, it may predict adult obesity.

Most babies thin out during toddlerhood and the preschool years as growth slows and become more active, but some remain obese.

Some researchers believe that weight setpoint is set in the first year of life, though.

Bottle-fed babies are 2 ½ times more likely to become obese than breastfed babies, although some studies refute this finding.

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Malnutrition

40-60% of world’s children are malnourished.Marasmus—a wasted condition caused by a

diet low in all nutrients. Appears in first year of life because Mother is too malnourished to produce healthy breast milk. Baby starves and is in danger of dying.

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Height & Weight Changes

At birth, the typical baby is 7.5 lbs. and 20 inches long.

First year of life: babies grow 10-12 inches and triple their body weight.

By age 2 for girls & 2.5 for boys, toddlers are roughly half as tall as they will be as adults.

2-year-olds still have proportionately larger heads than adults do because toddlers have nearly full-sized adult brains to go with their small bodies. (Cephalocaudal trend of development)

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Child with marasmus

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Kwashiokor

Caused by an unbalanced diet very low in protein

Usually strikes after weaning, about 1-3 years of age

Common in areas of the world in which children get enough starchy foods but too little protein.

Body starts breaking down its stores of protein reserves, causing extreme abdominal swelling and listlessness.

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A child with kwashiokor

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Failure to Thrive (FTT)

General consensus that it should be based on growth alone; weight and height remain consistently far below normal (bottom 3% of height & weight).

Accounts for 3% of pediatric hospital admissions.

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Two types of FTT

Organic 30% of cases Problem is usually a gastrointestinal disease or

sometimes a problem with the nervous systemNon-organic

Much more difficult to diagnose and treat Associated with poverty, neglect, poor parenting,

lack of love Usually present by 18 months of age Babies show signs of marasmus (wasting away)

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Parental Profile of Non-Organic FTT

Associated with serious caregiving deficitsParents alternate between periods of hostility,

impatience, avoidance, and coldness.Often seen in orphanages

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Two babies with Failure to Thrive Syndrome

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Neurological Changes

NO COMPUTER CAN MATCH THE BRAIN POWER OF THE AVERAGE 3-YEAR-OLD.

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At birth

Brain stem controls the 27 reflexesMedulla and midbrain are the two more

highly developed brain structures. They regulate vital functions (heartbeat, respiration, attention, sleeping, waking, elimination, and head and neck movements).

Least-developed part of the brain is the cortex, the gray matter that is involved in perception, body movement, thinking, and language.

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Changes in Brain Development

Synaptogenesis—the creation of synapses (connections between neurons) happens rapidly in the cortex in the first two years.

Creation of synapses is responsible for the nearly tripling of brain weight during first two years.

Brain development is not smooth and continuous. An initial burst of synapse formation during the

1st year is followed by a pruning of synapses in each area of the brain as redundant pathways and connections are eliminated and the wiring is made more efficient.

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More about Pruning

Doesn’t occur in all parts of the brain at the same time.

Example: Synapses in language centers reach maximum density at around 3 years old whereas synapses in the occipital lobe (visual cortex) are maximally dense when an infant is 4 months old.

A 1-year-old actually has denser dendrites and synapses than an adult does. Even at age 4, synaptic density is twice that of an adult’s.

Pruning occurs in spurs throughout childhood and adolescence.

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Plasticity

The ability of the brain to reorganize itself and “heal itself; the ability of the brain to change with experience, both good and bad.

Because young children have denser dendrites and synapse than an adult has, they have greater plasticity and can recover more from a brain injury than an adult can.

Flip side of plasticity: the child is especially vulnerable in the 1st 3 years of life. “Use it or lose it.”

Needs sufficient stimulation and good nutrition for maximal brain development.

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Myelinization

This is the process of creating the myelin sheath around axons (a fatty protein coating called myelin that covers the tail of the neuron).

Helps transmit messages more efficiently from the brain to other parts of the body.

Myelinization is dependent on dietary fat and is most rapid in the first two years after birth but continues at a slower pace throughout childhood & adolescence.

Follows a cephalocaudal, proximodistal pattern. (Babies get control of their hands before their feet, hands before fingers, etc.)

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ONCE THEY GET ON THE MOVE, LIFE AS YOU KNOW IT IS OVER.

Motor Development

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Dynamic Systems Theory (2006; 2013)

A theory that says that infants assemble motor skills for perceiving and acting.

They perceive something in the environment that motivates them to act. Then they use their perceptions to fine-tune their movements.

Motor skills, therefore, represent solutions to the infant’s goals.

Motor development is not a passive process in which genes control which skills are learned in which sequence; the infant actively puts together a skill to reach a certain goal. Nature and nurture work together.

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Two kinds of motor development

Gross motor development Control over actions that help the infant get around

the environement (crawling, standing, walking)Fine motor development

Smaller movements such as reaching, grasping, and holding crayons

Cephalocaudal trend occurs (motor control of head occurs before control of arms and trunk, which comes before the limbs.

Proximodistal trend is also evident: control of head, trunk, and arms is more advanced than control of hands and fingers.

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Fine motor skills

Onset of reaching and grasping marks a significant achievement in infants’ ability to interact with environment and reach goals.

Pincer grasp is a special milestone, usually reached around the same time the infant starts crawling.]

Infant will then start to pick up everything in sight (and try to eat it).

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Motor Skill Milestone Chart

Motor Skill Average Age Reached

90% reach

Holds head erect/steady

6 weeks 3 weeks-4 months

Lifts self with arms while on tummy

2 months 3 weeks-4 months

Rolls from side to back

2 months 3 weeks-5 months

Rolls from back to side

4.5 months 2-7 months

Sits alone 7 months 5-9 months

Crawls 7 months 5-11 months

Pulls to standing 8 months 5-12 months

Stands alone 11 months 9-16 months

Walks alone 12 months 9-17 months

Scribbles 14 months 10-21 months

Walks up stairs 16 months 12-23 months

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Sensory Development: Vision

All senses are fairly well-developed at birth except for vision.

Newborn’s visual acuity is about 20/600 because the visual centers in the brain are not fully formed yet, nor are the structures of the eye.

Color vision doesn’t occur until baby is 1-2 months old.

Vision improves remarkably by 4 months.6 months: visual acuity is about 20/40.Depth perception develops by 3-4 months of age.

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Visual Cliff Experiment (depth perception)

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Taste and Smell

Same capacities for taste and smell as adultsCan discriminate Mom’s smell from another woman’sWill turn away from unpleasant odors. (They like

vanilla & strawberry but don’t like rotten eggs or fish.)

By 6 days old, they prefer the smell of their mom’s breast pad to a clean pad.

Prefer sweet tastes (as do adults). Start to like salty taste around 4 months, which helps

them accept solid food.Can learn to like food they once hated.Dislike bitter things, which is probably an adaptive

since bitter-tasting substances are more likely to be poisonous.

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Newborn’s response to 4 different tastes (sweet, salty, sour, and bitter) 90 minutes after birth

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Hearing

Newborns can hear a wide range of soundPrefer complex tones such as noises and voices

instead of pure tonesBiologically programmed to respond to the sounds

of any languageCan respond to subtle distinctions in speech soundsEspecially like high-pitched, expressive voices that

rise in tone and the end of phrases & sentences (baby talk)

Newborns express a preference for the Cat in the Hat if they heard it in utero. (Fetus can hear by 33-34 weeks.)

Newborns turn toward a familiar caregiver’s voice within a few days of birth.

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Pain

Infants do experience pain.Infants who experienced severe pain as

newborns (as in circumcision) showed a greater pain response to routine vaccinations later in infancy.

Newborns have more resiliency in getting over painful events, however.

Circumcised boys often sleep deeply after the procedure, probably as a coping mechanism.