NEUR 2.4 - Brain Plasticity

• Spreading Activation Model

  Theory: Neurons represent a specific concept + share connections with neurons that represent related concepts + activation of 1 neuron
• Neuroplasticity

  The brain's ability to change its organisation through experience and learning
• Our brain is constantly changing with experience and learning, through changes in the immense network we have of synapse connections
• Ramon y Cajal's contribution

  "neurons do not regenerate"
• Synaptogenesis

  The creation, strengthening, weakening of neural connections
• Hebbian Learning

  "neurons that fire together, wire together" - Neurons that share connections together in a chain and fire their action potentials from 1 neuron to the next will strengthen connection every time those neurons fire together
• Neuroplasticity example - instruments

  Experience over a long period with sensation through the fingertips is causing an expanding of the hand area on the sensory cortex 
• Neuroplasticity example - Model stroke that affects their motor cortex 

  1.  Outcome - Maladaptive plasticity (actually gets worse): Stopped using/lack of use - area representing hand gets smaller
  2. Brain reorganisation: Good hand restrained, forced to use impaired hand - area of the cortex representing the hand started to expand, even beyond areas that previously were connected to control of the hand = other areas taking over function in compensation for damaged areas, growth of the hand on motor cortex associated with improved function
• Neuroplasticity example - Brain re-organisation in blind people


  Brain areas lacking their normal input can take new functions with use