Lecture 17 Review Flashcards
What’s the difference between short-term and long-term memory?
short term
- aka working memory
- close to sensory information, active information buffer
long term
- relatively permanent
- requires consolidation (long lasting change in neuron function)
What are the types of amnesia?
retrograde = before the event anterograde = after the event global = both
What’s the difference between declarative memory and non declarative memory?
- Declarative memory is something you can consciously report
- nondeclarative memory is something you learned about but do not remember the events that cause the plasticity in circuits to change for learning
• i.e. classical conditioning, procedural memory, etc.
How does synaptic modification play a role in learning?
- learning involves mostly with changing synaptic connectivity
- coincident neural connectivity is key in wiring the brain
•neurons that fire together will wire together
•out of sync will lose the link
What role do glutamate receptors play in synapse plasticity
- AMPA, NMDA, and metabotropic glutamate receptors are key to plasticity
- they must be coincident with extracellular glutamate and internal depolarization
Describe HM and how he was significant to learning and memmory
- epileptic man who was cured by removing the foci
- had declarative memory deficits
•could not form new memories
•short term memory intact but long term memory lost
• specific disruption of consolidation
•implicit memory was normal, procedural memory was normal
Describe the role that the medial temporal lobe has in declarative memory
Critical for declarative memory
- delayed non-matching example monkey experiment. memory decreased over time
- hippocampus receive input from the entorhinal cortex, outputs through the fornix
What structure is central for amnesia?
Peri-rhinal (PR) cortex
What role does the hippocampus have in memory?
- very involved in remembering places, navigation, and specific places
- roles in emotional regulation
- navigation requires interaction with entorhinal cortex
- closest link is to relational memory - linkage between stimuli
How is long term potentiation produced?
- Produced by high frequency stimulation of CA3 projections in CA1
- synapse must be active at the same time that a postsynaptic CA1 neuron is depolarized
- repeated coactivation of synapses = firing together makes them linkes = cooperativity
How is long term depression produced?
Low frequency stimulation of CA3 projection in CA1
- produces weaker synapses
How does AMPA and NMDA receptors affect LTP?
AMPA
- LTP can be produced either by increasing function of existing AMPA receptors through phosphorylation or by adding more AMPA receptors to the membrane of the synapse
NMDA
- the amount of NMDA receptors can determine if LTP or LTD will occur
- weakening/strengthening is input specific
How does calcium affect LTP
high [Ca] favors LTP
What role does CaMKII playin neural plasticity?
- it is critical for neuroplasticity
- it can autophosphorylate NMDA-mediated efflux of Ca for long periods of time
•this allows for long-term changes in cellular function to occur - acts as a molecular switch for long term changes
What role does protein synthesis play in memory in the hippocampus?
- all long term memory requires protein synthesis
- transcription factors like CREB seem to be involved
•CaMKII can phosphorylate CREB which induces transcription