Week 3 & 4: Development Flashcards
What are the 3 stages of prenatal development?
Germinal stage: 0-2 weeks
Embryonic stage: 2-8 weeks
Fetal stage: 9 weeks - birth
What occurs during the germinal stage of prenatal development?
the one-celled zygote divides into two cells, then 4, and so on; the zygote migrates down the fallopian tube and implants itself on the wall of the uterus (about half of zygotes don’t complete this journey)
What occurs during the embryonic stage of prenatal development?
the implanted embryo continues to divide and its cells begin to differentiate; the embryo has arms, legs, a beating heart, and the beginnings of female reproductive organs (if it is a male embryo, it begins to produce testosterone, which will masculinize the sex organs)
What occurs during the fetal stage of prenatal development?
the fetus has a skeleton, muscles, fat, digestive and respiratory systems, axons and dendrites; myelination begins at this stage and continues until adulthood
A newborn’s brain is ___% of its adult size.
25%
Why are babies born with an underdeveloped brain?
- To allow the baby to pass through the birth canal
- To allow the brain to develop within the environments in which it functions, gaining the unique capacities that each environment requires and the ability to adapt
What is a teratogen, and what are some examples?
any substance that passes from mother to unborn child and impairs development; examples include mercury in fish, lead in water, paint dust in the air, alcohol, tobacco, etc.
What is Fetal Alcohol Syndrome (FAS)?
a developmental disorder that stems from heavy alcohol use by the mother during pregnancy; children born with FAS have a variety of brain abnormalities and cognitive deficits
What evidence suggests that fetuses “listen”?
- Newborns will suck more vigorously when they hear the sound of their mother’s voice than when they hear a female stranger, suggesting they are familiar with their mother’s voice prior to birth
- Newborns who listen to strangers speaking two languages will suck more vigorously when they hear words from their mother’s native language, indicating they are already familiar withs its tempo and rhythm
- Babies’ cries are also influenced by the cadence of their mothers’ native language; for example, French newborns cry with a rising pitch and German newborns cry with a falling pitch
Define infancy
the stage of development that begins at birth and lasts between 18 and 24 months
How far can newborns see, and what is the significance of this distance?
20-30 cm - the distance between a mother’s face and a nursing infant’s eyes
How do researchers know that infants can see?
Infants habituate (respond less intensely each time a stimulus is presented) to visual stimuli
What are motor reflexes? Name some examples observed in newborns.
motor responses that are triggered by specific patterns of sensory stimulation
• Rooting reflex: causes infants to move their mouths towards any object that touches their cheek
• Sucking reflex: causes them to suck and object that enters their mouth
Reflexes present at birth seem to disappear in the first few months as infants learn to execute more sophisticated behaviour
What is the cephalocaudal rule?
“Top-to-bottom”: the tendency for motor skills to emerge in sequence from the head to the feet
What is the proximodistal rule?
“Inside-to-outside”; the tendency for motor skills to emerge in sequence from the centre to the periphery
Name some factors that influence the timing of the development of motor skills in infants
- Incentive for reaching
- Body weight
- Muscular development
- General level of activity
What is a scale error, in terms of infant development?
a disconnect between an infant’s motor and perceptual skills (ex. trying to slide down a miniature slide; they understand what to do with a slide as far as motor skills, but their ability to perceive that the slide is miniature is not coordinated with their behaviour)
What are Piaget’s four stages of cognitive development?
- Sensorimotor stage (birth to 2 years)
- Preoperational stage (2 to 6 years)
- Concrete operational stage (6 to 11 years)
- Formal operational stage (11 years and up)
What occurs during the sensorimotor stage of cognitive development?
- Infants are focused on using their ability to sense and their ability to move to acquire information about the world
- Infants construct schemas (theories about the way the world works) by exploring their environment, which allows them to predict what happens next after an action
- Assimilation: when infants apply their schemas in novel situations
- Accommodation: when infants revise their schemas in light of new information
- Object permanence: the fact that objects continue to exist even when they are not visible; does not develop until after the first few months of life
What occurs during the preoperational stage of cognitive development?
children develop a preliminary understanding of the physical world
What occurs during the concrete operational stage?
children learn how actions (operations) can transform the concrete objects of the physical world
What is conservation, when it comes to cognitive development?
the understanding that the quantitative properties of an object are invariant, despite changes in the object’s appearance (i.e. can tell that a tall, thin glass of water and a short, wide glass of water hold the same volume); develops in the concrete operational stage
What occurs in the formal operational stage of cognitive development?
children learn to reason about abstract concepts; childhood ends what formal operations begins, and people in this stage are able to reason systematically about abstract concepts (liberty, love, hypotheticals, counterfactuals, etc.)
Define egocentrism
the failure to understand that the world appears different to different people; a hallmark of the preoperational stage