Learning

• While the gross topology is stable, the synaptic strength is relatively dynamic.
• Short and long term potentiation and depression change the efficiency of synapses almost constantly.
• LTP and LTD is relatively long lasting; it's an open question, but the changes last from between months and years.
• Synaptic changes seem to be based on the firing behaviour of the neurons that are connected.
• The Hebb rule is largely accurate and states:
  if a neuron tends to cause another to fire, the synapse that connects them is strengthened.
• This seems to be the driving force behind biological learning.
• There is a lot of work in understanding these learning rules, both theoretical and biological.