LTP

Read pages 575 - 592

LTP

• A persistent strengthening of synapses based on recent patterns of activity.

review

• Graded potential

• Action potential

• EPSP

Schaffer collaterals of CA3 pyramidals onto CA1 pyramidal.

• If high frequency train of stimuli (AP) get LTP, evident as a long-lasting increase in EPSP amplitude.

• LTP occurs in many other regions of the brain: cortex, amygdala, cerebellum

LTP is state-dependent

• LTP occurs when the post synpatic response is quick and large.

• E.g. application of post synaptic current

• The state of the membrane potential of the post synaptic cell.

• Strong temporal linkage of pre and post synaptic events

LTP input specificity

• Only activated synapses are affected

• Applies to memory.

LTP is associative

• In one pathway is weakly activated during stimulation, then that synapse will be strengthened as well.

• Selective enhancement

• Cellular analogue of associative learning, but expected of all neural networks

LTP

• State dependent - the NMDA receptor needs depolarization to remove Mg inhibition

• Input specific -NMDA channels open only at stimulated synapses

• Associative - the depolarization at the neighboring synapse can affect an non potentiated synapse.