Topic 7 - brain development Flashcards
what does brain development involve
complex process linked with behavioural, emotional, cogntive, and overall maturation that progresses throughout childhood, adolescence, and into adulthood
hwo does brain growth occur
~80% of adult size at 2yo
occurs through glial cell development
developing synapses between neurons
hwo many neurons are we born with
~100 billion
same number as adulthood
why is early childhood important (2-7yo)
see large gains in cognitive, motor, and sensory function and improvements in behaviour
fine tuning connections and keep the ones that make sense/are helpful
in what order does grey matter mature in the frontal lobe
from back to front of the frontal lobe
why does grey matter mature back to front
motor control needed first (back)
executive function needed later (front)
occurs first in S1
last areas to develop are higher association areas (dorsolateral PFC - exec function)
when does peak grey matter volume occur relative to males and females
earlier in females
later in males
what is the relationship between grey matter and white matter changes
as grey matter decreases in volume, white matter increases in volume
when is the max white matter volume
no max
continuous process
what causes the continuous expansion
presumed to be partially due to progressive myelination of axons by oligodendrocytes
what is the difference in white matter through the lifespan
young adult = start of white matter increase
middle age = peak myelin = peak conduction rate
old age = start to lose myelin = slower conduction
what do changes in myelin basic protein tell us
myelin can be disrupted after a concussion
causes decrease in conduction speed
same task = more nutrient delivery, bigger activation for the same task
what supports changes in cognition and behaviour
ongoing development of brain structure and function
CBF may also be relevant (supplies blood and nutrients to the brain)
how do CBF levels change in males and females
early puberty = similar between males and females (decline at the same rate)
puberty = diverge with significant sex differences
males = CBF declines until late adolescence
females = declines until mid adolescence, shows increases after (higher blood flow from estrogen increase)
