Chapter 23 - Development and Plasticity Flashcards
What are the three approaches to studying brain development
- correlate brain development with behavioural development
- the reverse = observe behaviour to predict what is occurring in brain development
- identify factors that influence both brain and behavioural development
What are the stages of brain development
- cell birth
- cell migration
- cell differentiation
- cell maturation (dendrite and axon growth)
- synaptogenesis (formation of synapses)
- cell death and synaptic pruning
- myelogenesis (formation of myelin)
Explain how neurogenesis drops with age
in both rats and humans, there are high levels of neurogenesis in the perinatal period, which drops with age
rate of neurogenesis is very low in adulthood in both
Why is cell death and pruning so important to development
eliminates excess neurons
What is the problem of predicting PFC injury in young kids
the PFC is the last cortical region to mature, therefore if injured at a young age, it will be difficult to predict what the results will be
Which cortical region is first to mature and which is last
sensorimotor cortex is first to mature
PFC is last
What is happening to the brain during adolescence
it is a time of extreme plasticity (for good and bad)
plastic to injuries and adapt BUT also highly sensitive to drug and addiction
What age is the onset of mental disorders
14 years old is a key time, start to see development when looking back, may not be obvious at first
How is cortical development related to cognitive function
negative correlation between cortical thickness and cognitive performance (as cortex thins, becomes more efficient)
increased white matter maturation increases function
What are unexpected results related to problem solving ability and brain development
kids are better at more complicated task of concurrent discrimination learning task compared to easier nonmatching sample learning tasks since this one requires the PFC and that is not yet developed
What are the environmental effects on cortical development (12)
- visual experience
- tactile experience
- epigenetics
- complex environments
- language
- music
- play
- parent-infant interactions
- stress
- gut bacteria
- SES
- colonialism
Why is tactile stimulation so important
alter brain and behavioural development that improves adult motor and cognitive function
correlates with increased synaptic space across the cortex
BUT HOW does tactile stimulation affect the brain
after injury, rubbing to feel better, produces FGF-2 which crosses the blood-brain barrier that changes the brain, is an epigenetic change
How do complex environments affect brain development
strongest ways to alter brain
dendritic length and spine density increase in complex environments
How does early language exposure change the brain
What is an explanation for why lower SES kids have a lower vocabulary (why the language areas develop differently)
quantity and quality of language exposure
thinner cortices = high language scores = associated with higher SES
How does adoption affect brain development
age is important
adopted at younger age show more recovery (before 18 months)
have smaller frontal lobe and lower IQ
How does music affect brain development
increases brain volume, improves school performance and IQ
best to have training young, but still shows an affect at older age (impacts neural activation)
How does play affect brain development
increases pruning and flexibility (plasticity) in PFC
How does stress effect brain development
increased stress results in lower connectivity in amygdala and hpc connections
How does gut bacteria affect brain development
- affect vegus nerve
- affects blood system
need bugs and therefore bacteria
How does colonialism affect brain development
decline in indigenous quality of life and poverty, life expectancy, incarceration, drug abuse, etc.
What is the Kennard doctrine
if you are going to have brain injury, have it early so the outcome is better
mostly applies to motor functions
What is the Hebb principle
brain injury earlier may be worse
PFC injury in early childhood resulted in poor outcomes
