Learning and memory: The neural substrate Flashcards
Procedural Memory
Implicit memory
Non Declaritive memory
Reflexive memory
Skills and habits that have been used so much they are autonomic: riding a bike
Information is found in the cerebellum for motor
and in the nucleus accumbens for non motor
Declaritive Memory and the two subdivisions
also known as explicit memory
The conscious recognition/recollecttion of learned facts and experiences
Episodic: memory of events
Semantic: memory of words, language and rules
What are three memories based on its duration
Short-term: lasts seconds to hours
Long-term: years
Working memory: recalling a fact or memory for use- it may be a subset of short-term memory
the neural mechanism for each of these is different
What are the two types of changes in synaptic functioning
Post-Tetanic Potention
Long term Potention
Post tetanic Stimulation
Brief high frequency discharge of presynaptic neuron
produces an increase in neurotransmitter release that lasts about 60 seconds
Increases in probablillity of action potentials in post synaptic cell
Mechanism: High level of stimulation allows more calcium to enter the terminal than can be dealt with
- this leads to more vesicles and more nerotransmitter release
- thus increasing the probablillity of action potentials in the post synaptic cell
Long Term Potention (LTP) and the two types of molecules calcium binds
a series of changes in the pre and post synaptic neurons of a synapse which leads to increased response to the released neurotransmitter
ie (EAA)
increase Na into the cell causing depolarization that leads to activation of the NMDA receptor allowing for Ca to enter the cell
this Ca binds to calmodulin which increases adenylate cyclase and cAMP which causes phosphorylation of an AMPA receptor
THis AMPA receptor will now allow more influx of Na+ in response to the EAA (neurotransmitter) on the post synaptic cell
also Calcium will bind calcineurin which activates Nitric oxide synthesis which increases production of nitric oxide
this nitric oxide will increase cGMP and NT release on the presynaptic cell
What are the changes of the structures of the neurons that affect the plasticity of the brain and some examples
Gain/loss of synapses
structural changes of dendrites
structural changes in the soma of the neuron
increase gene transcription of CREB in both the pre and post synaptic cells
- Proteins produced:
- NT synthetic enzymes
- NT receptors
- Proteins required for growth and synapse formation
What is significant about blocking protein synthesis in neurons
Learning and the formation of new memories can be blocked by blocking protein synthesis
What is the 4 step process of creating Declaritive (Explicit) Memories
1) Encoding
2) Storage of the information
3) Consolidation
3) Retrieval
what is Encoding
Attending to new info (focus and attention)
linking it to previous memories
Emotion is important component
what is storage of the information
Retention of information over time
-short term memory
LOng term capacity is not limited
What is the anatomical substrate and physiological substrate of short term memory
Hippocampus
Parahippocampal gyrus
Orefrontal cortex
all considered the long term Potention or the physiological substrate
how does Alzheimers play a factor in the short term memory
in short term memory there are projections to the neocortex and the amygdala via the nucleus basalis of Meynert (cholinergic projections)
this is a target of the alzheimers disease because there neurons are not meeting the threshold of the presynaptic cell to drive the creation of a new memory
WHat is our temporary storehouse for memory
The hippocampus
Parahippocampal gyrus
Prefrontal cortex
or
LTP
What is consolidation
Process of making a memory permanaent
involves physical changes in synaptic structure and making new synapses
what is the anatomical requirement for consolidating a memory
Hippocampus
Temporal lobes
Papez circuit
What is the Papez circuit and how does it become a long term memory
Hypothalamus/mammillary bodies to the anterior thalamus to the cingulate cortex and then to the hippocampus and then repeat
the repetition of the memory through the papez circuit sets up the conditions for long term potention and neuronal plasticity
once it becomes a long term memory the limbic system is not required to access the memory
Where does the long term memory go after the limbic systerm
the memory is now stored in the area of cortex related to the modality of the individual cortex
visual with the visual cortex
What is retrieval
Recalling or using the memory
Bringing it into working memory
can be modified/lost at this point
Where does the reassembling of a long term memory occur and in what order and what is the significance of that order
Neocortex
Parahippocampal regions
Hippocampus
INformation of each component sent to parahippocampal regions
then the information is sent to the hippocampus where the memory is reconstructed
then the information is sent back through the parahippocampus to the cortex
THe second time through the parahippocampus is important for prolonging the cortical trace of the memory
Working memory and the three component model
Central executive phonological loop (words associated with it) visuospatial loop (look like)
what are the anatomical locations of the three component model
central executive: Prefrontal cortex
Phonological loop: Brocas and wernickes
Visuospatial loop: Occipital cortex associated with vision
Where is the detailed memory of a space stored and its impact on memory
in the hippocampus using special pyramidal cells in CA1 known as place cells
the spatial map serves as an anchor for the reconstruction of memory
purpose of place , grid cells, and border cells in the spatial map
neurons that are active at specific places especially at places you get an reward
Grid cells found in the entorhinal cortex make a hexagonal grid of your location
Border neurons care about a border of the location