Adolescent brain

• What key regions undergo significant changes during adolescence ?

  Amygdala and corpus callosum, cerebellum, prefrontal cortex and frontal lobe
• cerebellum during adolescence

  • Grows in volume
  • Synaptic pruning eliminates weaker synaptic connections
  • strengthening of neural circuits with other regions such as the amygdala and the frontal lobe
• corpus Callosum during adolescence

  • thickens through the process of myelination
  • messages are passed between hemispheres more quickly, meaning increased efficiency when supporting complex cognitive functioning
• Amygdala during Adolescence

  • grows in volume
  • synaptic pruning = elimination of weaker neural pathways
  • increasing neural connections to other brain structures
• Frontal lobe/prefrontal cortex

  • Gradual myelination of neurons increases white matter and improves connectivity with other regions of the brain including the amygdala
  • synaptic pruning leads to more efficient neural networks which leads to better ability to plan, organise and make decisions
• impact on behaviour

  myelination and synaptic pruning in the cerebellum and frontal lobe primary motor cortex) result in:

  • voluntary motor movements becoming more coordinated and precise
  • faster acquisition of fine and gross motor skills
• impact upon emotions

  changes to amygdala during early adolescent leads to heightened reactivity/sensitivity to emotional stimuli

  • compared to adults or younger children teen experience: intense emotions, more mood swings, increased sensitivity to stressors leading to anxiety and irritability
• impact on behaviour

  • heightened sensitivity/reactivity of amygdala also motivates teens to seek our rewarding experiences
  • heightened reactivity of amygdala and slow rate of maturation in frontal lobe/prefrontal cortex to impulsive or risk taking behaviours
• impulsive behaviours include?

  substance use, unprotected sex, reckless driving
• in later adolescence:

  • its not all reactivity and impulsivity
  • increased neural connections between the cerebellum, amygdala and frontal lobe leads to greater emotional regulation
  • impulsive behaviours decline
• why do impulsive behaviours decline?

  • greater emotional regulation
  • improvements in decision making and reasoning from maturation of frontal lobe/prefrontal cortex and the corpus callosum
  • maturation of the prefrontal lobe/pre frontal cortex leads to greater empathy and better social interactions with family and friends