neural plasticity Flashcards
Neural Plasticity
Neural plasticity is the ability of the brain’s neural structure or function to be changed by experience throughout the lifespan.
This may involve a single neuron, a pair of neighbouring neurons or entire networks of neurons.
For example, if a monkey is trained to push a lever with a finger several thousand times a day, the brain tissue which controls that finger changes to reflect the experience.
Long-Term Potentiation & Long-Term Depression similarities
Long-term potentiation and long-term depression are enduring (long-lasting) changes in synaptic strength that are brought about by specific patterns of activity at the synapse.
These activity-dependent changes are thought to play a critical role in learning and subsequent memory formation.
Long Term Potentiation
Long-term potentiation (LTP) refers to the long- lasting strengthening of synaptic connections, resulting in enhanced or more effective synaptic transmission.
Basically, the effect of LTP is to improve the ability of two neurons — a presynaptic and a postsynaptic neuron — to communicate with one another at the synapse
The more that the connection is activated, the more the connection is strengthened.
When LTP happens:
dendrites become bushier
more receptor sites are developed
more neurotransmitters are released in to the gap.
Long Term Depression
Long-term depression (LTD) is the opposite ofLTP; that is, a long-lasting decrease in the strengthof synaptic transmission.
This results from prolonged low level stimulation of pre- and postsynaptic neurons.
It is believed that LTD may be just as importantfor learning and memory as LTP.
The weakening or elimination of unused synapses through LTD may prune unimportant or unwanted connections, leaving only the important connections that have been strengthened through repeated use by LTP.
The process occurs as if the rule ‘use it or lose it’ is being followed.
Sprouting,
Sprouting the ability of dendrites or axons to develop new extensions or branches.
Rerouting
Rerouting the ability of a neuron that is connected to a damaged neuron to create an alternative synaptic connection with an undamaged neuron.
Pruning
Pruning the elimination of synaptic connections that are not adequately activated.
