Unit 4 Psychology
Plasticity of
the brain
Brain Plasticity
• The brain’s ability to reorganise and relocate
neural pathways based on new experiences
and learning.
• Also known as neuroplasticity.
Developmental Plasticity
• The process of strengthening new and frequently activated
neural connections through experience with the
environment
• Also facilitates the elimination of weak connections that are
not used.
• The neural changes occur as a result of learning and
development of the organism
Application: Circuit Formation vs Circuit Pruning
When a baby is born, there are around 2500 synapses for each neuron in the
cerebral cortex. After a few years, the number of synapses increases to
around 15000 per neuron (Circuit Formation), then reduces to around 8000
per neuron in adulthood – as old and disused connections are eliminated
(Circuit Pruning).
Adaptive Plasticity
• The process whereby brain functions can be relocated to other
areas of the brain.
• Changes in the brain’s neural structure that enable adjustment:
– Due to experience
– To compensate for the loss of function sustained (usually as a result of
damage)
– To maximise remaining functions in the event of brain damage.
Application:
– If an individual suffers a loss of function due to damage of the neurons
in the brain, then adaptive plasticity can occur as neurons in the area
surrounding the damage can change and take on the role the
damaged neurons would normally control, in order to compensate for
some of the lost function.
– Hence, the individual has the potential to regain some functions lost
after brain damage has been sustained, although it is rare for
someone with brain damage to recover all of their lost functions.
Adaptive Plasticity and Age
• Children’s brains show greater
plasticity than adults, this
might explain why children
learn languages faster than
adults
• In general, the later in life a
loss of function occurs, the
more limited the capacity for
adaptive plasticity.
– Loss can be:
• Damage to neurons of the brain
• Damage to a body part that can
no longer communicate with the
brain
Reason:
Neural Growth and development
slow with age.