PSYCHOBIOLOGY: lifespan changes

Question 1

state the 3 critical periods in development

Answer 1

• language
• perception
• motor skills

Question 2

which 4 critical periods can children not master?

Answer 2

• complex abstract concepts eg international law
• self control
• time perception
• planning (delay instant gratification)

Question 3

what is the critical period?

Answer 3

• substantial rewiring
• begins when critical structures are in place and ends when changes are not possible
• critical period is more restricted if the change is more elaborate

Question 4

how does brain injury cause neuron death?

Answer 4

• lack of oxygen and glucose due to blocked blood vessel
• drowning in blood from ruptured blood vessel

Question 5

describe how phantom limb sensations occur

Answer 5

• amputation causes loss of input to corresponding part of cortical map
• synaptic connections are silent, making room for nearby axons
• active pathways take over silent ones and create a phantom sensation from stimulation of body parts with adjacent cortical representation

Question 6

how does ageing affect the brain?

Answer 6

• loss of muscle mass and bone density
• cortex and subcortical structure atrophy (death of neurons and loss of synaptic connections)
• decline in fitness and motor skill so increases reaction times
• decrease in memory capacity
• decrease in mental flexibility

Question 7

what does it mean for a cortical neuron to be more developed

Answer 7

• more, larger dendritic branches
• longer axons with more collaterals
• thicker cortex