biosocial development: first years (chapter 5)
Tom is a 1-year-old boy who weighed 8 pounds at birth. he is now MOST likely to weigh about _____ pounds.
24
nine-year-old Naledi, who is severely underweight for her age, often eats only a bowl of rice a day. based on this information, Naledi is MOST likely suffering from a form of malnutrition called:
wasting
body changes (to year 1)
- birthweight doubles by the fourth month and triples by 1 year; there is a substantial variation - typical newborn grows 10 inches by age 1 - average at birth: weight 7 pounds; length 20 inches
brain development
- brain is the fastest growing organ - brain growth affects later cognition - head-sparing occurs when body is physically challenged
course of development
- cephalocaudal (head-down) and proximodistal (center-out) direction - sitting, standing, crawling, walking, walking backward, running, jumping
hearing
- develops during the last trimester of pregnancy - most advanced of the newborn's senses - speech perception by 4 months after birth
immunizations are unsafe for:
- embryos exposed to rubella - newborns - people with compromised immune systems
adequate nutrition
- for every infant disease (including SIDS), breast-feeding reduces risk and malnutrition increases it, stunting growth of body and brain - breastfed babies are less likely to develop allergies, asthma, obesity, and heart disease - as the infant gets older, the composition of breast milk adjusts to the baby's changing nutritional needs
smell & taste
- function at birth - rapidly adapt to the social world - related to family and cultural preferences - may have evolutionary function
SIDS (sudden infant death syndrome)
- in her research with young children, Beal found that almost all SIDS babies she studied were sleeping on their stomachs - stomach sleeping is a proven, replicated risk - other risks include low birthweight, being male, smoking parents, soft blankets and pillows, bed-sharing, winter, and a variety of abnormalities - most SIDS victims experience several risks
perception follows sensation
- infants' brains especially attuned to their own repeated social experiences and perception occurs•Infant brain and auditory capacity to hear sounds in the usual speech range - the parts of the cortex dedicated to the senses develop rapidly
effects of chronic malnutrition:
- learning suffers - diseases are more serious - some diseases result directly from malnutrition - marasmus - kwashiorkor
seeing
- least mature sense at birth - newborns focus between 4 and 30 inches away - experience and maturation of visual cortex improve shape recognition, visual scanning, and details - binocular vision occurs at 3 months
surviving in good health
- most child deaths occur in the first month - in developing nations, 99.9 percent of 1-month-olds live to adulthood - educated women have fewer, healthier children
patterns of infant sleep:
- newborns average 15-17 hours a day - over the early weeks, REM sleep and traditional sleep declines rapidly - slow-wave sleep increases - individual differences due to maturation, genes, and environment - caregiver response to infant behavior during sleep hours also impacts sleep patterns - insufficient sleep may be a problem for parents and infant
problems include:
- no effective vaccine found for AIDS, malaria, cholera, typhoid, and shigellosis - many rural areas of the world are not reached
pain
- pain and temperature are often connected to touch - some people assume that even the fetus can feel pain: others say that the sense of pain does not mature until months or years later - many NICU have adopted pain and stress reducing practices
body changes (from year 1 to year 2)
- physical growth slows - at age 2, one-half adult height; one-fifth adult weight
immunization
- primes the body's immune system to resist a particular disease - contributes to reduced mortality and population growth; herd immunity - successes (smallpox, polio, measles)
touch
- sense of touch is acute in infants - although all newborns respond to being securely held, soon they prefer specific touches
exuberance & pruning
- the brain contains great excess of neurons at birth - a newborn brain has fewer dendrites, axons, and synapses and much less myelin than an adult brain - a great but temporary increase in the number of dendrites develop in an infant's brain during the first two years of life (transient exuberance) - unused dendrites whither postnatally to allow space between neurons in the brain, allowing more synapses and thus more complex thinking
baby Mason is 2 months old and sleeps 8 1/2 hours per day. about _____ in 20 infants sleep(s) less than 9 hours each day.
1
Sally's weight has tripled since she was born. this gain is typical of a child who is:
1 year old
baby Andre sleeps 13 1/4 hours per day. based on information provided in the textbook, Andre is probably _____ months old.
4
at the age of 2, Maude is 2' 8" tall. by the time she reaches adulthood, her height will likely be approximately:
5'6
by age 2, a baby's brain weighs almost ______ percent of its adult weight.
75
prefrontal cortex
area of the cortex at the very front of the brain that specializes in anticipation, planning, and impulse control
the _____ sleep stage is characterized by flickering eye movements, dreaming, and rapid brain waves.
REM (rapid eye movement)
myelin
axon coating that speeds neuron transmission
neurons
a neuron is one of billions of nerve cells in the central nervous system (CNS) - communication within CNS begins with neurons - most neurons are created before birth, at a peak production rate of 250,000 new cells per minute in mid-pregnancy (Purves et al., 2004) - in infancy, the human brain has billions of neurons.
when U.S. infants are grouped by ethnicity, _____ infants tend to walk the earliest.
african american
cultural variations
all healthy infants develop skills in the same sequence, but the age of acquisition varies variations influences: genes, cultural patterns, nutrition, caregiving patterns
severe social deprivation
anecdotal evidence with human children and research with other mammals confirms that isolation and sensory deprivation harm the developing brain
neurotransmitter
brain chemical that carries information from the axon of a sending neuron to the dendrites of a receiving neuron
limbic system
brain parts that interact to produce emotions, including amygdala, hypothalamus, and hippocampus
hippocampus
central processor of memory, especially memory for locations
norms
defined standards of typical performance (these represent average measurements; individuals vary)
malnutrition
condition in which a person does not consume sufficient food of any kind that can result in several illnesses, severe weight loss, and even death
both of Brian's parents are deaf, and he is deaf also. American Sign Language is the primary language of communication in Brian's home. Vladimir and his family live in Russia, and their primary language is Russian. if we were able to look at some of the structures in Brian's and Vladimir's brain, we would probably see some physical differences. these differences would be accounted for by which of the following?
experience-dependent brain functions
two English-speaking men are from geographically distant regions. one was brought up in Manchester, England, and the other in Dallas, Texas. they both speak the same language but differ extensively in their accent, vocabulary, and inflection. despite their cultural differences, both men developed language skills because language is:
experience-expectant
stunting
failure of children to grow to a normal height for their age due to severe and chronic malnutrition
dendrite
fiber that extends from a neuron and receives electrochemical impulses transmitted from other neurons via their axons
axon
fiber that extends from a neuron and transmits electrochemical impulses from that neuron to the dendrites of other neurons
which of the following are characteristics of REM sleep?
flickering of the closed eyes and rapid brain waves
the average newborn doubles her birthweight in:
four months
a newborn is lying in his crib. someone across the room speaks. how will the newborn react to the voice?
he will turn his head in the direction of the voice
at 12 months of age, Toni was malnourished. her body stopped growing, but her brain did not. This supports the concept of:
head-sparing
the biological protection of the brain when malnutrition temporarily affects body growth is known as:
head-sparing
Meena cannot be vaccinated because of her allergies, but she is protected to some degree from catching childhood diseases because of _____ immunity, which means that at least 90 percent of people in her local community have been immunized.
herd
the production of antibodies is stimulated by:
immunization
percentile
number that indicates rank compared to other similar people of the same age (percentiles range from zero to 100)
synpase
intersection between the axon of one neuron and the dendrites of other neurons
which of the following is a disease caused by chronic malnutrition in childhood in which a protein deficiency makes the child more vulnerable to other diseases, such as measles, diarrhea, and influenza?
kwashiorkor
young children who are small for their age and who have swollen legs and bellies are becoming more common in camps for internally displaced persons in African nations torn by civil war. these children are suffering from:
kwashiorkor
Batoor was born in war-torn Afghanistan. malnutrition caused him to waste away soon after his birth; he passed away at the age of 4 months. Batoor suffered from _____.
marasmus
perception
mental processing of sensory information when the brain interprets a sensation
dynamic sensory systems
most important experiences are perceived with interacting senses in dynamic systems: - sensations facilitate social interaction and comfort - by 6 months, infant are able to coordinate the senses
maturation of the brain's _____ cortex is necessary for walking.
motor
the text suggests that immunization rate is ______ correlated with infant mortality rate.
negatiely
MOST specifically, an infant's lack of self-control can be explained by the immaturity of the _____ cortex.
prefrontal
cortex
outer layers of the brain where most thinking, feeling, and sensing occurs
stress & the brain
overabundance of stress hormones damages later brain functioning
Michael was subjected to much stress as an infant due to repeated episodes of family violence. now, as an adult, he shuts down emotionally whenever he starts to experience any type of stress. this response may be because during infancy stress hormones in his brain were:
overproduced
gross motor skills
physical abilities involving large body movements, such as walking and jumping
motor skills
physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin - learned abilities to move some part of the body, in actions ranging from a large leap to a flicker of the eyelid - shaped by culture and opportunity
necessary stimulation
playing, allowing varied sensations, and encouraging movement are necessary for brain connections
the text suggests that infant mortality is ______ correlated with fertility rate.
positively
Jeremy is trying to save money for college. he saves half of the money he earns from his part-time job. he has set a goal to save enough money to pay for his dorm fees for his first year. these behaviors demonstrate that Jeremy's _____ cortex has matured.
prefrontal
cortisol
primary stress hormone whose fluctuations affect human emotions
the process through which unused and misconnected dendrites atrophy and die is called:
pruning
hypothalamus
responds to amygdala and hippocampus to produce hormones that activate other parts of brain and body
pituitary
responds to signal from hypothalamus by hormone production
sensation
response of a sensory system (eyes, ears, skin, tongue, nose) when it detects a stimulus
hair cells in Gino's basilar membrane detect a series of high-pitched tones. Gino recognizes the ringtone assigned to calls from his mother. Gino remembers that he had neglected to call his mother the night before as he had promised. Gino's detection of the tones illustrates:
sensation
receptors that are highly sensitive to sweetness are active on Malia's tongue. bitterness receptors are also active, but to a lesser extent. Malia recognizes the taste of cola and considers her resolution to reduce her soda consumption. the action of Malia's taste receptors is called:
sensation
intervention
shaken baby syndrome is a life-threatening injury that occurs when an infant is forcefully shaken back and forth (this motion ruptures blood vessels in the brain and breaks neural connections)
sensations and motor skills furthers three goals:
social interaction, comfort, learning
wasting
tendency for children to be severely underweight for their age as a result of malnutrition
dynamic systems underlying motor skills
three interacting elements underlying motor skills: - muscle strength - brain maturation - practice
sensory development
typically precedes intellectual and motor development