Learning and Memory Flashcards
What is procedural memory?
Aka: implicit memory, non declarative memory, reflexive memory Skills and habits that have been used so much they’re automatic Motor skills come from cerebellum while habits come from nucleus accumbens
Declarative Memory?
Aka Explicit memory, conscious recognition recollection of learned facts and experiences
- Episodic: memory of events
- Semantic: memory of words language and rules
Working memory?
Recalling a fact or memory for use, may be a subset of short term, physiologically similar to short term
What is Plasticity and how does it occur?
- Alterations in the CNS based on use
- might be synaptic fxn that is altered
- might be changes in physical structure of neurons such as more synapses or branches
What are the two main forms of plasticity and their subsets?
- Changes in synaptic functioning
- Post-tetanic potentiation
- Long term Potentiation
- Changes in structure of neurons
- gain or loss of synapses
- structural chagnes in dendrites
- changes in soma
What is Post tetanic potentiation?
- Brief high frequency discharge of presyn neuron
- Produces increase in NT release that lasts 60 seconds
- increase probability of AP in post synaptic cell
How does post tetanic stimulation work?
- High level of stimmulation allowed more calcium to enter the terminal than it could handle. It is temporarily overwhelmed, so there is more Ca to bind docking proteins causing more NT release
Long term potentiation?
- Series of changes in pre and post synaptic neurons of synapse that leads to increased response to released NT
- usually follows a strong stimulation
- EAA induces LTP (others can too)
How does LTP work?
- More calcium is in post synaptic neuron due to NMDA and non NMDA receptors
- Calcium activates calcineurin activating NOS to increase NO which goes back to presyn cell increasing cGMP resulting in more NT release
- Increase gene transcription related to CREB
- Calcium also binds calmodulin increaseing AC and cAMP resulting in phosphorylation of AMPA receptor allowing more Na in
What is link between LTP and changing structure of neurons?
CREB bc it results in gene transcription
How can forming new memories or learning be blockedc?
jBlocking protein synthesis
What four steps are needed for creating declarative memory?
- Encoding
- Storage of info
- Consolidation
- Retrieval
Describe encoding.
- Attending to new information
- Linking it to old memories
- Emotion is important
Describe storage.
- Retention of info over time
- short term used initally
- long term capacity not limited
What are the anatomical structures for short term memory?
- hippocampus
- parahippocampal cortex
- pregrontal cortex
What process creates short term memories?
LTP
What is the “temporary storehouse for memory”?
Short term memory
Consolidation?
Making a memory permanent by changing synaptic structures
What structures does consolidation require?
Hippocampus and temporal lobes and Papez circuit
Describe the papez circuit
- Hypothalamus/Mammillary bodies: physical responses
- Anterior thalamus: sensory info coming in
- Cingulate cortex: emotion
- Hippocampus: short term memory
How do we consolidate memory from short to long term?
Create long term potentiation and repeatedly activating the synapses that are involved in the memory (the papez circuit!)
- repeatedely goes through papez circuit setting up conditions required to induce LTP and neuronal plasticity back to the cortex
- eventually limbic system isn’t needed for the memory
What structures does the retrieval process require?
- Neocortex
- Parahippocampal region
- Hippocampus
Where are specific memories such as visual, smell, or auditory stored?
Long term memories are stored in the area of cortex releated to the modality of the memory
- Ex: visual stored in visual cortex
During retrieval process information related to each compoenent of meory is sent to the ___. Then to___ and back to ___.
- Parahippocampal region
- the hippocampus
- Back through parahippocampal region to cortex
Why does memory travel back through the parahippocampal cortex?
Important in prolonging the life of cortical trace of the memory
What is the three component model of working memory?
- Central executive: IDing what you need
- Phonological loop: words and rules needed
- Visuospatial loop: visual memories
All feed to central executive!
What areas of the brain can the three component model pieces be found?
- Centarl executive prefrontal
- Phonological loop brocas and wernikes
- Visuospatial loop occipital cortex associated with vision
What is spatial memory?
- Detailed memory of space is stored in the hippocmapus using special pyramidal cells in CA1 known as Place cells
- Spatial map serves as an anchor for reconstruction of memory
What inputs do the place cells recieve?
Place cells are high order neurons active only at specific places
- Grid cells in the entorhinal cortex that create a map of place you are in, triagnonal or hexagonal grid
- Head direction cell
- fire when you remember what direction you turned in
- Border cell: fire at borders
