Postnatal cerebral development

Question 1

What is neuroplasticity?

Answer 1

the ability of the brain to change continuously throughout an individuals life

Question 2

Why does the volume of the brain quadruple between birth and adulthood?

Answer 2

• synaptogenesis
• myelination
• dendric branching

Question 3

Experimental studies on cats

Answer 3

• early closure (1st week) of one eye causes distribution of cortical neurons to prefer the open eye
• when 1 eye closed from 12-18 weeks not the same effect because first 3 months is critical period

Question 4

define critical period

Answer 4

period during development in which particular skill is most readily required

Question 5

experimental studies on monkeys

Answer 5

• monocular deprivation affects width of ocular dominance columns in visual cortex
• critical period = first 6 months

Question 6

what is the critical period for learning our native language?

Answer 6

12 years

Question 7

explain the visual pathway in humans

Answer 7

• geniculostriate system
• info passed through dorsal lateral geniculate nucleus to primary visual cortex
• left + right primary VC receives info from both eyes

Question 8

example of neuroplasticity in adults

Answer 8

taxi drivers in London have bigger hippocampi than non-taxi drivers (navigation spatially requires hippocampus)
-people who have become blind post-puberty: visual cortex responds to Braille (somatosensory system involved)

Question 9

How does neuroplasticity continue through adulthood?

Answer 9

• axonal sprouting: axons from somatosensory system invade tissue that was previously used by visual system
• adult neurogenesis: part of brain manages to produce neurons during adulthood