30 Memory and Hippocampus Flashcards
Name the three different types of memory.
procedural, declarative and working memory
Describe the nature of procedural memory
aquired memories are embedded in procedures or occurs as changes in how pre-existing cognitive operations are carried out (usually spared by amnesia)
Describe the nature of declarative memory.
storage of explicit information, can be brought to the mind as a proposition or image- this includes facts, lists and data of convential memory, usually impared with amnesia
Describe the nature of working memory
process by which task-relevant information is kept on-line, appropriately updated in order to optimize performance (mental chalkboard)
What brain region is thought to mediate working memory?
prefrontal cortex
Name two types of learning.
associative learning and non-associative learning
Describe the process of associative learning
the process of forming associations among stimuli and responses and is often further divided into classical and operant learning
Describe the process of non-associative learning.
refers to simpler types of learning in which behavioral repsonse to a give n stimulus changes with repeated presentations of the stimulus (ie. Habituation and sensitization)
What type of learning is classical conditioning (Pavlovian)
classical conditioning is a type of associative learning
How is one classically conditioned?
through a process whereby a previously neutral stimulus, upon temporal association with a reflex-eleciting stimulus, gains the ability to elicit the reflex repsonse
What type of learning is operant conditioning?
operant conditioning is a type of associative learning
How does one undergo operant conditioning?
through a process where a consequence is made contingent upon a specific behavior
Describe 3 different types of consequences in operant conditioning.
consequences that serve to increase the probability of the behavior (reinforcement) consequence that serves to reduce the probability of the behavior (punishment) and consequence of behavior is the removal of an unpleasant stimulus (negative reinforcement)
What is plasticity and how does it differ from memory?
in the context of this class, plasticity refers to experience induced changes in molecular processes and network organization of the brain, as induced by exposure to salient stimuli, stimulus-stimulus associations or action-outcome contingencies
The hippocampus is particularly important in the formation of what types of memory?
required for laying down declaritive memory as well as processing for remembering spatial locations
The amydgala is particularly important for what type of memory?
mediates memory attained by classical conditioning, especially fear conditioning or biologically significant events
What is the dorsal striatum important in?
dorsal striatum mediates the formation of reinforced stimulus-response associations
Describe the overal organization of hippocampal tracks. (logitudinally, traverse running, corical connections???)
hippocampal structures are organized in a transectional as well as a tranverse pattern which is thought assist in forming associative connections
Which area of the hippocampus serves as the interface between brain and hippocampus?
entrorhinal cortex
Where do information tracts head from the entrorhinal cortex?
information tracts run directly to the dentate gyrus (perforant pathway) or also directly to CA fields
How does information travel from the CA fields of the hippocampus back to other cortical regions?
CA 3 send information to CA1 along schaffer collateral pathwyays and CA1 projects to the subiculum which projects to deep layers of the entrorhinal cortex (CA3 > CA1 > Sub > EC deep)
Where is the entrorhnial cortex located?
hippocampal fomation is embedded within the temporal lobe, immediately adjacent to a specialized part of the cortex termed the entorhinal cortex
Which fibers come together to form the fornix as information exits the subiculum?
fibers from the subiculum gather into the alveus, which collects increasingly thicker fibers into the fimbria and the fibers of fimbria are collected within the fornix
Generally speaking where does the fornix run?
from the hippocampus to the basal forebrain (mammillary bodies)
What are the two branches of the fornix and what do they carry
precommisural branch which innervates septal nuclei and post commisural branche which splits to innervate the hypothalamus and the thalamus
The extensive processing and integration throughout the entire hippocampal formation is throught to be the basis of what?
formation of complex declarative memory representations
Coritical interconnections with the hippocampus are usually with what type of cortex?
connections primarily with high level association cortex
What is the significance of “place cells”?
firing of cells at distinct places withing the hippocampus is thought to be invovled in spatial memory and navigation
Describe the Two Stage Model Memory Theory
in order to precent interface with preexisting long-term memories, newly encoded memories are initially stored in an intermediate buffer from where these memories are gradually transferred to long-term store in an off-line process
Experiments displaying hippocampal sharpwaves preceeding prefrontal spikes during slow wave sleep are significant how?
they suggest the connetion between SWS and memory consolidation
What is Hebbian Synapse?
idea that relative efficacy of particular synapse would be increased if that particular synapse was persistantly active in firing its target (cells that fire together wire together)
Pathways that develop demonstrate plasicity are highly conserved across species, what is the general basis of plasicity?
certain connections between neurons have become stronger due to upregulated processes in those cells
What upregulated processes/molcules are important to develop memories that can outlive cell turnover?
upregulation of molecules common in species including : MAPK, CREB-1, CRE (ERK pathway), PI-3K, CaMKII etc.
