Long-term potentiation (LTP) is a lasting increase in the strength of communication between neurons. This lesson introduces synaptic plasticity, explains why LTP matters for learning and memory, and traces the ideas and experiments that led to its discovery.
A synapse is a junction where one neuron communicates with another. In neuroscience, long-term potentiation (LTP) is a persistent strengthening of synapses, based on recent patterns of activity. After an LTP-inducing pattern, a presynaptic neuron can produce a larger response in its postsynaptic target than it did before.
All flashcards
Early-phase LTP (E-LTP)
An early form of potentiation involving kinase activity and rapid changes to existing AMPA receptors or their insertion into the postsynaptic membrane.
Late-phase LTP (L-LTP)
A longer-lasting phase of potentiation that requires gene transcription and protein synthesis.
Input specificity
The general tendency for LTP to strengthen the synapses that receive appropriate activity rather than spreading to all inputs on a neuron.
Synaptic tagging and capture
A hypothesis in which activated synapses form temporary tags that capture plasticity-related proteins produced in response to activity.
Retrograde signaling
A proposed signal traveling from a postsynaptic cell back to a presynaptic cell to alter presynaptic function.
Quiz questions
What distinguishes associativity from cooperativity in LTP induction?Answer: Associativity pairs a weak input with a strong input; cooperativity combines multiple weak inputs.
Which activity pattern is required for anti-Hebbian LTP?Answer: Presynaptic depolarization paired with relative postsynaptic hyperpolarization.
What did AP5 demonstrate in Schaffer collateral LTP in hippocampal CA1?Answer: Blocking NMDA receptors with AP5 prevented LTP in that pathway.
What cellular processes are required for late-phase LTP?Answer: Gene transcription and protein synthesis in the postsynaptic cell.
In a study of inhibitory avoidance learning, what did occlusion mean?Answer: Synapses potentiated during training could not be further potentiated by experimental LTP-inducing procedures.