Week 3 Flashcards
Developmental Systems Theory
Development occurs within a system of interacting levels
-Environment, behavior, neural activity and genetic activity
Epigenesis
any functional change in the genome that does not involve an alteration in the DNA sequence
-gene expression
-does not change DNA code but can be passed on through generations
Rat grooming experiment
-high grooming moms offspring have lower stress response and become HG mom
-low grooming moms offspring have higher stress response and become LG moms
-Methylation prevents gene from creating receptors causing poor regulation of stress
-methylation is equal at birth and by day 6 demethylation in high groomed pups occurs
Genotype environment theory
PASSIVE EFFECTS
when genetically related parents provide a rearing environment for their child
EVOCATIVE EFFECTS
when a child elicits responses from others that are influenced by his/her genotype
ACTIVE EFFECTS
When a child’s genotype influences the types of environments he/she selects
Conduct disorders
-difficulty with self-regulation combined with fear or anger which leads to dysregulated behavior
-emerge by 8 years: more common in boys
-onset before age 10 = more aggressive
-result of genetics and antisocial family members, deviant peers, inconsistent discipline, parental insensitivity, family stress
-treatment: consequence behavior therapy
-family oriented treatment most effective
-associated with low MAOA activity (can mediate affects if high activity)
Multisensory effects
QUESTION: do baby ducks recognize species specific maternal call
-originally seen to have innate preference but they just listen to the call while in egg and develop that preference during prenatal development
what are the 5 stages of brain development
- Formation of the Neural Tube
- Neurogenesis
- Migration
- Differentiation
- Cell and Synaptic Pruning
Formation of the Neural Tube
-Occurs 18-24 days after conception
-flat neural plate folds to create tube
-failure to properly close can cause birth defects (spina bifida)
Neurogenesis
-Neurons form in one small region of neural tube
-10-28 weeks after conception
-4000 neurons/sec at peak
-New neurons are typically not formed after birth
Migration
-Neurons move to permanent locations in the brain - via glial cells
-faulty migration associated with various disorders (Cerebral palsy or epilepsy)
Differentiation
NEURONS
-grow in size
-produce more dendrites and longer axons
-become specialized
SYNAPTOGENESIS
-process in which synapses form begins
INCREASED MYELINATION
-fatty sheath that protects and covers axons
-speeds conduction velocity
-reduces leakage of electrical impulses
-occurs early in infancy and up until early adulthood
Cell and Synaptic Pruning
-Removal of neurons and synapses that are not being used
-results in increased efficiency in remaining neurons/synapses
-“use it or loss it” phenomenon
Prenatal Hearing
-At 16 weeks gestation, a developing fetus perceives sound outside womb through fluid-filled ears
-fetus learns focal rhythms and patterns which prepares them to perceive sounds in their native language
-mostly hear the mother
Should parents read to their prenatal “students”?
no evidence to suggest that this stimulates brain development
-music is a stimulating pattern but only rhythm is filtered into the embryonic fluid
Newborns of deaf parents
-No evidence that hearing children of deaf parents experience language delay (5-10 hours of exposure/week sufficient)
-demonstrate same auditory preferences
DeCasper & spence Dr.Seuss study
-mothers instructed to read Dr.Seuss out loud while pragnant
-after birth, newborns prefer listening to Dr.seuss over other stories and prefer their mothers voice over other readers
Prenatal tasting study
-3 groups of women who planned to breastfeed
A. drink carrot juice 4 days a week in the last 3 weeks of 3rd trimester, switch to water after birth
B. Drink water during 3rd trimester, switch to carrot juice after birth
C. Control group: just water
-When babies were started solid goods, given cereal made with water or carrot juice
-infants exposed to carrot juice showed fewer negative facial expressions and enjoyed carrot cereal more
Facial movements of fetus studied in Utero: prenatal tasting
-used 4D ultrasound scans
-moms given flavored capsules: carrot (non-bitter) or kale (bitter)
-control group: not given anything
-Kale made grimacing face
-carrot smiled
Teratogens
Agent that causes abnormal prenatal development
Thalidomide
-sedative prescribed for morning sickness in 1950s
-babies born with deformities in arms, legs, hands, fingers
-10,000 infants affected before it was pulled from market
-Dr.Kelsey, medical officer of health for US FDA in 1960 refused approval
Diseases effect on development
-Can pass through placenta and attack the fetus directly
Eg Cytomegalovirus (Type of Herpes), rubella, syphilis, Zika
-May attack at birth from the lining of the birth canal
Eg Genital herpes, AIDS, zika
Nicotine
-constricts blood vessels and thus decreases oxygen and nutrient flow to fetus through the placenta
-increased risk of miscarriages, premature births, prolonged developmental impacts
- children show impaired cognitive skills, delayed language, behavioral problems
- Adolescents show impaired memory
Alcohol
FASD: Fetal Alcohol Spectrum Disorder
-broader categorization
FAS: Fetal Alcohol syndrome
FAS
-Women who drank at least 5 ounces per week during pregnancy
-Slow growth, heart problems, characteristic facial features (small head, thin upper lip, short nose, wide spaced eyes)
-Actual brain damage prenatally causing cognitive deficits
