Brain Plasticity

The brains ability to change and adapt

Developmental Plasticity:

• Brain development is not complete when you are born

• During the first years the brain grows rapidly

  • Neurons mature and send out multiple branches which increases the number of synaptic connections

• At birth each neuron has around 2,500 synapses- by 3yrs it increases to around 150,000 synapses per neuron - synaptogenesis

• As we mature connections not used are deleted- Synaptic pruning

Plasticity:

• It requires environmental input to continue developing

• For the first 6yrs it goes through periods of enhanced plasticity

Adult plasticity:

• Exposure to new stimuli- the brain creates new connections

• Axon sprouting: Brain areas increase in size the more you use them

• Study by Maguire: Hippocampus and memory

  • Found it increases in grey matter of taxi drivers

  • A correlation was found between time as a taxi driver and the volume in the right posteriour hippocampus

Positive plasticity:

• When the brain becomes more efficient and organised

• Timetables- repeated practice cause connections to become stronger and recall needs less effort and we make less errors

• MRI: Meditation increases grey matter within the left hippocampus

Negative plasticity:

• Negative thoughts can promote neural changes associated with depression and anxiety

• Drugs and alcohol: Rewire the reward system in the brain

• MRI: 17 teenagers with depression

  • Smaller left hippocampal volume