Memory 3 Flashcards
(32 cards)
LTP has been most frequently studied in
The rat hippocampus
Hebb argued WHAT was the basis of long term memory?
Changes in efficiency of synaptic transmission
Bliss + Lomo, 1973
A single, low-intensity pulse was delivered to
The performant path
Bliss + Lomo, 1973
A single, low-intensity pulse was delivered to the performant path. How was the response recorded?
Extracellular electrode in hippocampus
Bliss + Lomo, 1973
A single, low-intensity pulse was delivered to the performant path. What was the purpose of this initial stimulation?
To determine initial response baseline
Bliss + Lomo, 1973
How was the LTP induced?
High-intensity, high-frequency stimulation (10 secs)
Bliss + Lomo, 1973
What did the granule cell layer of the hippocampus show 1 week after LTP?
Synapses were still potentiated
2 KEY properties of LTP (Hebb)
- Last for a long time
2. Only develops if firing of pre-synaptic is followed by firing of post
If the firing of a pre-synaptic cell is not followed by the firing of a post-synaptic cell, will LTP develop?
No
Critical factor in LTP is the
Co-occurrence of pre and post synaptic cells
LTP can be elicited by low levels of stimulation that
Mimic normal neural activity
LTP effects are most prominent in structures
That have been implicated in learning
Many drugs that influence learning and memory have
Parallel effects on LTP
The induction of MAXIMAL LTP (rats) blocks…
Learning of Morris water maze
Mutant mice that display little hippocampal LTP have difficulty…
Learning the morris water maze
LTP is a three part process…
Induction
Maintenance
Expression
The ____ receptor is prominent at the synapses at which LTP is commonly studied
NMDA
NMDA is a receptor for
Glutamate
What is the principle excitatory neurotransmitter?
Glutamate
80% of synapses in the brain are
Glutamenergic
TWO requirements for NMDA receptor response
- Glutamate must bind
2. Post-synaptic neuron must be partially depolarised
NMDA receptors
If the post-synaptic neurons are partially depolarised, their calcium channels
Will open wide when glutamate binds to their receptors
Co-occurence of firing
When natural, low-intensity stimulation is applied, the post-synaptic neurons
Don’t fire
LTP isn’t induced
A consistent finding has been that _______ inhibitors block the induction of LTP
Protein kinase inhibitors