infant, child and adolescent brain

Question 1

where do the amazing capabilities of the human brain arise from

Answer 1

• stoundinly intricate communication among billions of interacting cells.

Question 2

schizophrenia

Answer 2

may occur because pathways in the brain and connections to it formed incorrectly in early life

Question 3

susceptibility to autism spectrum disordes

Answer 3

• genes that infleunce brain development could play a role in this

Question 4

baby’s brain three trimesters after development in the womb

Answer 4

• after birth, baby’s brain continues to grow and develop

- avg weight of a newborn human baby is about 370 grams, slightly less than a pound

Question 5

average weight of an adult brain

Answer 5

3 pounds with about 86 billion neurons

Question 6

newborn baby brain

Answer 6

• product of 40 weeks of brain development

- rapid development conitunes after birth

Question 7

growth rate after birth

Answer 7

• immediately after birthm the growth rate of the whole brain is about 1 percent per day
• rate slows as baby ages
  reaches about 0.4 percent per day by three months after birth

Question 8

baby at 90 days old

Answer 8

• overall brain volume is 64 percent larger than at birth

Question 9

fastest growing brain region of the brain at 90 days old

Answer 9

• cerebelllum
• it is more than double its volume at birth
• cerebellum has the most neruons
• helps with learning mtor skills and movements
• important for babies learning to grab thing and eat good

Question 10

what is the overall increase in brain volume the result of

Answer 10

• a large number of brain cells growing, multiplying (proliferating), maturing (differentiating) and migrating

Question 11

neruon increase during the first three months of life

Answer 11

• the number of neruons in the cortex increases 23-30 percent,
• dendrites and axons of these neruons grow longer, make many connections (sunaptogensis), making the brain bigger

Question 12

what is another way the brain grows in volume

Answer 12

• cells known as glia grow, multiply, and provide myelination (by oligodendrocytes)
• brain’s white matter looks white because of all the myelin-wrapped nerve fibers

Question 13

five years after birth

Answer 13

• child has reached about 90 percent of its adult size

- leaves plenty of room to grow during childhood, adolescence, and early adulthood

Question 14

two year old’s brain

Answer 14

• number of connections between nerunons (synaptic densirt) increases rapidly
• has 50 percent more synspases than an adult brain
• still only about 80 percent the size of an adult brain
• too many synapses for the brain to maintain

Question 15

when does synaptic pruning occur

Answer 15

• occurs at around two years old, during the first couple of years after birth
• there are too many synapses for the brain to maintain
• synapses use energy and resources
• brain must reduce the number and fine-tune these connections through synaptic pruning
• it is shaped by the toddler’s experiences as they grow

Question 16

synpatic pruning

Answer 16

• allows weaker connections to diminsh while stronger synpases that are activated more often will grow and stabilize

Question 17

humans are born with more developed brains than other animals

Answer 17

FALSE

• compared to other animals, humans are actually born wit less developed brains
• human brains also take longer to mature
  e. .g. squirrel monkeys reach their adult brain size at 6 months old

Question 18

do humans develop more in the womb orout>?

Answer 18

• human brains grow and develop extensively after birth
• developing brains are more easily shaped by environment and experience
• this is an advantage because It helps us adapt appropriately to thee surrounding environment.

Question 19

criticial periods

Answer 19

• inputs from sensory, motor, and even emotional aspects of life experiences affect how the brain develops and adapts to a given environment.

Question 20

what factors exert a great amount of influence during critical periods

Answer 20

• genes and environemnt exert strong influences

- they form nerual circuits that affect learning and behaviour

Question 21

what does shaping of connections involve

Answer 21

• neruonal cell death
• synpatic pruning
• these processes occur in the embryo and in early postnatal life

Question 22

changes in nerual connections

Answer 22

• cahnges during the critical periods they coincide with higher rates of learning - e.g. a toddler learning to run or to speak multiple languages

Question 23

teenage brain

Answer 23

• many changes
• amazing capacity to learn
• more synaptic pruning
• stronger connections beat out weaker ones in a process called competitive elimination
• brain is improving its connections

Question 24

what happens to neurons in the teenage brain

Answer 24

• improving connections :
• neruons extending their dendritic branches
• myelination of axons increases (esp in frontal lobes)

Question 25

longitudinal studies

Answer 25

• ## esp important bc they reveal how early life events and environment can affect outcomes later in life e.g. education, or risk for disease

Question 26

second cirtical period

Answer 26

• adolescence

- more complex functions of the brain develop and can be infleucned by the environment and experience

Question 27

adolescent brain from an MRI

Answer 27

• ## shows an increase in white matter volume (esp in corpus calosucm)

Question 28

what does the growth of the corpus c. indicate

Answer 28

• enhanced learning capacity in adolescenes due to increasing connections

Question 29

what contributes to teenager’s risky behavirours.. increased risk-taking, and sensation seeking, and aspects of enhanced learning ability,

Answer 29

• enhanced connetions
• changes in the brain’s reward systems
  changes in the balance between frontal and limbic systems
  -

Question 30

frequent drug use

Answer 30

• associated iwth damage to brain regions important for cognitive functions such as memory, attentions and executive functioning

Question 31

white matter and addiction

Answer 31

• DTI shows that alacohol and drug abuse can cause significant changes in gray and white matter in adolescents
• adolescents who did that studd had reduced gray matter volume and reduced white matter integrity

Question 32

binge-drinking during adolescnece

Answer 32

• lower brain activity
• les sustained attention
• poorer performance on a working memory task

Question 33

when do human brains develop until

Answer 33

• until thirty years old

- different brain regions show diff rates of growth and maturation