Developmental Psychology Flashcards
Epigenetic view
development is the result of an ongoing, bidirectional exchange between heredity and the environment
Critical period
limited period of time during which an organism is biologically prepared to acquire certain behaviors but requires the presence of appropriate environmental stimuli to occur (ie imprinting)
Sensitive period
human critical period; there are optimal times for the development of certain capacities during which the individual is particularly sensitive to environmental influences, but those capacities can develop earlier or later to some degree; the boundaries of sensitive periods are more flexible
Genotype v phenotype
genotype: genes
phenotype: observable characteristics affected by both genes and environment (ie intelligence, personality)
Canalization
traits that are highly influenced by genotype and relatively resistant to environmental forces (ie motor milestones)
Range of reaction
traits that exhibit a range of reaction; genotype sets boundaries on the range of possible phenotypes, and environmental factors determine where in that range the phenotype falls (average intelligence in poverty vs enriched environments)
Secular trends
generational differences in physical growth and development (ie declining age of menarche in industrialized countries)
Gene-environment correlation
associations that are often found between people’s genetic makeup and the environmental circumstances exposed to; niche-picking is the tendency of people to seek out environments compatible with genetic makeup (ie musical talent)
Heritability index
used to estimate the degree which a particular trait can be attributed to genetic factors
Polygenic inheritance
traits determined by multiple gene pairs rather than a single gene pain (ie skin color, eye color, temperament, intelligence, susceptibility to cancer)
Gene-linked abnormalities
- Huntington’s disease: single, autosomal dominant gene, so a child of an afflicted parent has a 50% chance of inheriting the disorder
- Phenylketonuria (PKU): recessive gene disorder
- Tay Sachs, sickle cell anemia, cystic fibrosis
Chromosomal abnormalities
Down syndrome: extra number 21 chromosome (trisomy 21)
- Prader-Willi syndrome: deletion on the paternal chromosome 15
- Klinefelter syndrome: extra X
- Turner syndrome: part of an X chromosome is missing
- Fragile X syndrome: weak site on the X
Teratogens
- substances and conditions that interfere with normal prenatal development, such as drugs, toxins, malnutrition, maternal infections, and maternal stress
- most common: alcohol (FAS), nicotine, cocaine, rubella (German measles), herpes simplex, cytomegalovirus (type of herpes), HIV, prenatal malnutrition, maternal stress
Prenatal development periods
Germinal period: conception fo implantation (8-10 days following conception)
Embryonic period: end of week 2 to end of week 8, most susceptible to structural defects
Fetal period: week 9 to birth, less affected by teratogens, but still can cause impaired organ functioning, delayed growth, and intellectual/emotional functioning
Birth complications
Prematurity (before 37 week), small for gestational age (<10th %ile), fetal distress
Brofenbrenner’s ecological model
microsystem, mesosystem (interaction between components of microsystem), exosystem (aspects the person is not in direct contact with), macrosystem (sociocultural), chronosystem (time, history)
6 characteristics that contribute to likelihood child will develop psychiatric disorder
severe marital discord, low SES, large family size, parental crime, maternal psych disorder, placement of child outside home
Brain development
- most neurons are present at birth
- post-birth: synaptogenesis, myelination
- brain begins to decrease in weight/neuron loss around age 30
- decline accelerates after age 60
Infant reflexes
- palmar grasp reflex
- Babinski reflex: infant extends big toe and fans out small toe when sole is stroked
- Moro/startle reflex: when in horizontal position, infant arches back, extends legs outward, and brings them back to body in response to head being allowed to drop or to sudden loud noise
- Rooting: infant turns head toward stimulation when cheek is stoked near corner of mouth
- reflexes are typically done within first 6 months as infants have gradual increase in voluntary control
Motor Skills: 1 month
Gross MS: turns head side to side when prone
Fine MS: strong grasp reflex
Motor Skills: 3 months
Gross MS: holds head erect when sitting, but head bobs; regards own hand
Fine MS: holds rattle, pulls at clothes, brings objects in hand to mouth
Motor Skills: 5 months
Gross MS: when sitting, holds head erect and steady, reaches and grasps, puts foot to mouth when supine
Fine MS: plays with toes, takes objects to mouth, grasps objects voluntarily
Motor Skills: 7 months
Gross MS: sits, leaning forward on both hands, stands with help
Fine MS: transfers objects from one hand to other
Motor Skills: 9-10 months
Gross MS: creeps, pulls to standing position when holding on to furniture
Fine MS: uses thumb and index finger to grasp