PS103 Childhood Development

Epigenetic Framework

Suggests that the environment can affect the expression of genes just as genetic predispositions can impact a person’s potentials.

Environment Correlations

Refer to the processes by which genetic factors contribute to variations in the environment. There are three types of genotype-environment correlations (passive, evocative, and active).

Passive Genotype-Environment Correlation

Occurs when children passively inherit the genes and the environments their family provides.

Evocative Genotype-Environment Correlation

Refers to how the social environment reacts to individuals based on their inherited characteristics (e.g., the way extraversion/introversion impacts how people interact with you)

Active Genotype-Environment Correlation

Occurs when individuals seek out environments that support their genetic tendencies. Also referred to as niche picking.

Genotype-Environment Interactions

Involve genetic susceptibility to the environment. Different genotypes have different phenotypes based on the environment.

Genes

Recipes for making proteins

Mitosis

The cell’s nucleus making an exact copy of all the chromosomes and splitting into two new cells

Meiosis

Cells used in sexual reproduction

Autosomes

22 pairs of chromosomes that are similar in length

Genotype

Refers to the sum total of all the genes a person inherits

Phenotype

Refers to the features that are actually expressed

Homozygous

When the same gene is inherited from both the mother and father

Heterozygous

When a different version of the gene is received from each parent

Dominant Gene

Express themselves even when the other type (recessive) is present

Recessive Gene

Express themselves only when paired with a similar version gene

Alleles

Different versions of the same gene

Polygenic

A characteristic that is the result of several genes

Genetic Disorders

Most are dominant-gene linked, but most are not serious or debilitating

Recessive Disorders (Homozygous)

The individual inherits a gene from both parents. If it’s just from one, they are a carrier but will not have the condition.

Autosomal Dominant Disorders (Heterozygous)

The individual only needs to inherit the gene change from one parent

Chromosomal Abnormatilies

Occurs when a child inherits too many or too few chromosomes

Germinal Period

From conception to implantation of the fertilized egg in the lining of the uterus (about 14 days).

Zygote

Fertilized cell containing the combined genetic information from both parents

Embryo

Starts around the third week, once the blastocyst has implanted into the uterine wall. It is multi-cellular, and blood vessels will not grow to form the placenta

Cephalocaudal Development

Growth during prenatal development that occurs from head to tail

Proximodistal Development

Growth during prenatal development that occurs from the midline outward.

Fetus

Referred to as this from about the 9th week until birth. Major structures are continuing to develop.

Teratogens

Environmental factors that can contribute to birth defects. There are four categories.

Physical Teratogens

Examples include saunas, hot tubs, or infections that raise a pregnant woman’s body temperature. Associated with neural tube defects, spontaneous abortions, and various cardiovascular abnormalities

Metabolic Conditions Affecting Pregnant Females - Teratogen

Abnormalities in the chemical process of producing energy from food. Malnutrition, diabetes, and thyroid disorders are examples.

Infections - Teratogen

Maternal infections (like rubella virus, herpes simplex virus, and syphilis)

Drugs and Chemicals - Teratogen

Impact varies based on the specific agent, amount of exposure, and timing. Radiation, heavy metals, insecticides/herbicides, prescription and OTC drugs, illicit recreational drugs, alcohol, cigarettes, nicotine, caffeine, and some vitamins

Amniocentesis

A procedure in which a needle is used to withdraw a small amount of amniotic fluid to test cells from the sac surrounding the fetus and later tested. Has risk of miscarriage.

Chronic Villus Sampling

A procedure in which a small sample of cells is taken from the placenta and tested. Has risk of miscarriage.

Hyperemesis Gravidarum

Severe nausea, weight loss, and possibly dehydration. Exact causes are unknown. Low risk of miscarriage but high risk of premature birth.

Ectopic Pregnancy

Occurs when the zygote becomes attached to the fallopian tube before reaching the uterus. About every 1 in 50 pregnancies, and rates are increasing.

Spontaneous Abortion

Experienced in an estimated 20-40 percent of undiagnosed pregnancies and in another 10 percent of diagnosed pregnancies. Usually due to chromosomal abnormalities and typically before the 12th week.

Preeclampsia

Also known as Toxemia. Sharp rise in blood pressure, leakage of protein into the urine because of kidney problems, swelling of the hands, feet and face during the third trimester

Most common complication. Can cause seizures (eclampsia), which is the second leading cause of maternal death in the US. Leading cause of fetal complications.

Eclampsia

When preeclampsia causes seizures. Second leading cause of maternal death in the US.

Maternal Mortality

About 1000 women die in childbirth around the world each day.

Infertility

Diagnosis given when a couple has been trying to conceive for a year and failed to conceive. Affects about 10-15 percent of couples in the US.

Apgar Assessment

Conducted one and five minutes after birth. Quick way to assess the newborn’s overall condition. Five measures are assessed: heart rate, respiration, muscle tone, reflex response, and color. Second one should indicate improvement with a higher score. Under a 5 for either is concerning.

Anoxia

Temporary lack of oxygen to the brain.

Preterm Baby

Born at less than 37 weeks gestation

Postmature

When babies are not born by 42 weeks gestation (two weeks post due date)

Vernix

White substance that newborns are coated in. Thought to act as an antibacterial barrier.

Thyroid Stimulating Hormone

The hormone that influences growth in the central nervous system (CNS).

Dendrites

Connections between neurons

Synaptogenesis

The formation of connections between neurons

Synaptic Blooming

Period of rapid neural growth that begins in the prenatal period and continues through infancy and toddlerhood

Sucking reflex

Infants suck on objects that touch their lips automaticall

Rooting reflex

Involves turning toward any object that touches the cheek

Palmar grasp

The infant will tightly grasp any object placed in its palm

Dancing reflex

Evident when the infant is held in a standing position and moves his feet up and down alternately as if dancing

Moro reflex

A sudden noise or loss of support to the neck causes the infant to spread out their arms and legs then quickly contract their limbs inward.

Tonic Neck

When lying on the back with the head to one side, infants will extend the arm and leg on that side while flexing the limbs on the opposite side

Stepping Reflex

Legs move in stepping-like motion when feet touch a smooth surface

Babinski Reflex

An infants toes will fan out and curl when the sole of the foot is stroked from heel to toe

Voluntary Movements

Involve the use of large muscle groups and are typically large movements of the arms, legs, head, and torso. Gross motor skills.

Gross Motor Skills

Voluntary movements that use the large muscle groups and are typically large movements

Milestones

Behaviors or physical skills seen in infants and children as they group and development that typically occur within normal range

2-Month Gross Motor Milestones

Able to hold head up. Begins to push up when lying on tummy.

Makes smoother movements with arms and legs.

4-Month Gross Motor Milestones

Holds head steady, unsupported

Pushes down on legs when feet are on a hard surface

May be able to roll over from tummy to back

Brings hands to mouth

When lying on stomach, pushes up to elbows

6-Month Gross Motor Milestones

Rolls over in brother directions (front to back and back to front)

Begins to sit without support

When standing, supports weight on legs and might bounce

Rocks back and forth, sometimes crawling backward before moving forward

9-Month Gross Motor Milestones

Stands, holding on

Can get into a sitting position

Sits without support

Pulls to stand

Crawls

1-Year Gross Motor Milestones

Gets to a sitting position without help

Pulls to stand, walks holding onto furniture (“cruising”)

May take a few steps without holding on

May stand alone

18-Month Gross Motor Milestones

Walks alone

May walk up steps and run

Pulls toys while walking

Can help undress self

2-Year Gross Motor Milestones

Stands on tiptoe

Kicks a ball

Begins to run

Climbs onto and down from furniture without help

Walks up and down stairs holding on

Throws ball overhand

Fine Motor Skills

More exact movements of the feet, toes, hands, and fingers. Can also be called small motor skills.

2-Month Fine Motor Milestones

Grasps reflexively

Does not reach for objects

Holds hands in fist

4-Month Fine Motor Milestones

Brings hands to mouth

Uses hands and eyes together, such as seeing a toy and reaching for it

Follows moving things with eyes from side to side

Can hold a toy with whole hand (palmar grasp) and shake it and swing at dangling toys

6-Month Fine Motor Milestones

Reaches with both arms

Brings things to mouth

Begins to pass things from one hand to the other

9-Month Fine Motor Milestones

Puts things in mouth

Moves things smoothly from one hand to the other

Picks up things between thumb and index finger (pincer grip)

1-Year Fine Motor Milestones

Reaches with one hand

Bangs two things together

Puts things in a container, takes things out of a container

Lets things go without help

Pokes with index finger

18-Month Fine Motor Milestones

Scribbles on own

Can help undress himself

Drinks from a cup

Eats with a spoon with some accuracy

Stacks 2-4 objects

2-Year Fine Motor Milestones

Builds towers of 4 or more blocks

Might use one hand more than the other

Makes copies of straight lines and circles

Enjoys pouring and filling

Unbuttons large buttons

Unzips large zippers

Drinks and feeds self with more accuracy

How far can newborns typically see?

Cannot typically see further than 8-16 inchesC

Colustrum

First breast milk produced during pregnancy and just after birth. Very rich in nutrients and antibodies.

When should solid foods be introduced?

Typically around 6 months, but every child is different.

Child must be able to sit with little or no support, have good head control, and open his mouth/lean forward when food is offered.

Infantile Marasmus

Starvation due to lack of calories and protein

Kwashiorkor

“The disease of the displaced child”

Often occurs after another child has been born and taken over breastfeeding. Results in a loss of appetite and swelling of the abdomen as the body begins to break down the vital organs as a source of protein

Milk Anemia

Milk consumption leads to a lack of iron in the diet. Calcium in milk interferes with the absorption of iron in the diet.

Failure to Thrive (FTT)

Occurs in children whose nutritional intake is insufficient for supporting normal growth and weight gain. Typically presents before 2 years of age, when growth rates are the highest