memory 1 Flashcards
describe declarative/explicit memory
- contents
- mechanism
“easy come, easy go”
- facts and events
- conscious recollection
location of declarative/explicit memory
- medial temporal lobe
- especially hippocampus
- diencephalon
non-declarative/implicit memory
- contents
- mechanism
“hard to learn hard to forget”
- procedural & classical conditioning
- without conscious recollection
what two factors make up non-declarative memory?
- procedural
- classical conditioning
what info and brain areas are involved with procedural and classical conditioning?
procedural
- skills and habits = striatum
classical conditioning
- skeletal musculature = cerebellum
- emotional responses = amygdala
what are the two ways that non-declarative conditioning is formed? define them?
non-associative
- change in behavioral response that occurs over time to a single stimuli
associative
- change in behavioral response that occurs due to formation of association between to events
what are the 2 types of non-associative learning?
habituation
- decrease response to meaningless stimulus
sensitization
- increase response to sensory stimulus
what are the 2 types of associative learning?
describe them?
classical conditioning
- stimulus evokes a response
instrumental/operant conditioning
- association of a response with a stimuli
describe working memory
- only last for seconds
- limited capacity
describe short-term memory
what is it like physically?
- last for hours to days
- large capacity
- physical change that fades with time
what can disrupt short term memory?
- ECT
- head trauma
- does not disrupt long term
describe long term memory
- unlimited capacity
- weeks to years
- stable despite head trauma
brain area for working memory?
- frontal lobe/pre-frontal cortex
what happens when frontal lobe is leisoned?
- issues with problem solving
- plan behavior
- wisconsin card sorting task/delayed response task
define consolidation?
storing memory in a permanent form
what is the consolidation process influenced by?
salience and emotion
what does the medial temporal lobe (MTL) include?
- hippocampus
- rhinal cortex
- amygdala
what is the medial temporal lobe critical for?
- declarative memory formation and storage
what does the lateral temporal lobe include?
- high order visual areas
- IT area that responds to complex object
what happens when the temporal lobe is electrically stimulated?
- complex experiences of memories
what happens when temporal lobe is damaged?
- amnesia
what are the types of amnesias?
retrograde
- forget past memories, usually graded in time
anterograde
- inability to form new memories
what parts of the brain were missing in patient HM?
- amygdala
- hippocampus
what did HM suffer from?
what remained?
what did he lack?
- absolute anterograde amnesia
- partial retrograde amnesia
- he had a good working memory
- could remember procedural tasks
lacked ability to consolidate
what does HM still having memory tell us?
memories are broadly distributed throughout the brain
- hippocampus may have to do with linking new sensory information and to older memories
what does delayed non-match task say about MTL?
- medial temporal lesions cause anterograde amnesia
hippocampus lesion + spatial memory?
(arm maze)
- can still learn task=procedural memory is fine
- but forgets which arm had the food=working or short term memory is impaired
bilateral hippocampus lesion + spatial memory?
(water maze)
- rat is unable to get better at finding platform
what cells are in the hippocampus specifically?
what do they respond to?
place cells
- responds to the place where the animal thinks it is
grid cells
- activate at many locations that can be laid out in a grid
where do grid cells get their input from?
entorhinal cortex
what is the cognitive map theory?
the theory that the hippocampus creates a map of the environment
large hippocampus =?
large navigation capacities
7 aspects of hippocampus?
1) consolidation
2) short term memory
3) spatial memory
4) link information
5) grids
6) selectivity for faces and objects
7) lesions may disrupt memory and spatial
what is reconsolidation?
- recall reactivates memories and they are stored again
- memories may be altered after reconsolidation
what does reactivating a memory do?
makes it plastic again, meaning it is susceptible to change
what can block memory formations?
- benzodiazepines
- ECS
keep going!
!
what do benzodiazepines do?
how do they work?
- they cause anterograde amnesia for events shortly after administration
- GABA-A receptors have benzodiazepines receptors
what does HDAC2 do?
shuts off plasticity genes
what is the effect of a HDAC2 inhibitor?
plasticity will be turned on and old associations can be altered
- think mouse, sound, shock experiment
