Learning and Memory Flashcards
what is learning and memory
L: acquisition of new information
M: retention of learned info
T.F. the way and place info is stored can change over time
T
what is the first division of categories of memory
explicit (declarative
implicit (non-declarative)
what are the divisions of declarative memory
semantic (facts)
episodic (events)
what are characteristics of declarative memory
easy to form and forget
accessible to conscious recollection
what is included in non-declarative memory
procedural memory: motor skills, habits
what are characteristics about non-declarative memory
requires repetition to form, less likely to be forgotten
doesnt need conscious recollection
what does procedural memory link
sensations to movement
learning a motor response in reaction to a sensory input
what are further categories of non-declarative learning
non-associative learning
- habituation
- sensitization
associative learning
- classical conditioning
- operant conditioning
what are other types of declarative memory
working memory
short-term memories
long-term memories
characteristics of short-term memories
stores facts and events
converted to long-term
disrupted by head trauma, electro convulsive therapy (ECT), intoxication
characteristics of long-term memories
recalled months or years later
less susceptible to disruption
characteristics of working memory
temporary storage, lasts seconds, sensitive to distractions, limited capacity, requires rehearsal to keep something in mind
where does working memory occur in the brain
neocortex, numerous brain locations
how can you improve working memory
chunking (grouping numbers (phone #))
how can we test working memory
wisconsin card sorting task and delayed-response task
what type of lesions can impair working memory
prefrontal cortex
what is amnesia
serious loss of memory and/or ability to learn
what types of amnesia are there
limited, dissociated, transient global, retrograde, anterograde
what is limited amnesia
most common, caused by trauma
typically occurs with non-memory cognitive deficits
what is dissociated amnesia
rare
no other cognitive deficits
what is transient global amnesia
sudden and short-lasting global amnesia resulting from temporal ischemia and causes memory gaps
what is retrograde amnesia
memory loss for things prior to brain trauma
can be all episodic M
typically most severe or recent events, then goes down
what is anterograde amnesia
inability to form new memories after brain trauma
learning could just be slower
affects most episodic M, procedural M is usually good
in most clinical cases, people suffer more of retrograde or anterograde amnesia
mixture of both
who taught rats to run rat mazes
karl lashley
what did karl lashley say/discover
cortical lesions produced memory deficits (rat maze)
lesion size>location correlates with deficit
speculated all cortical areas contribute equally (equipotential)
what was kept and what was rejected from karl lashleys theories
equipotential disproved
memory traces/engrams can be widely distributed in the brain
what did D.O. Hebb believe
external events are represented in a network of simultaneously active cortical cells
what (in cells) accounts for working memory
cell assembly, reverberatory activity in the network of cell
how does consolidation happen according to Hebb
by growth process
cells that fire together, wire together
what does the engram of cell assembly involve according to Hebb
widely distributed linked cells
neurons involved in sensation and perception
what happens to the cell assembly when a visual stimulus like a circle appears
circle activates a cell assembly
they continue to be active in absence of circle
repeated activity strengthens connections creating an engram/memory
partial activation of the engram can recall the entire memory
memory could be retained even after partial damage to the engram
where are declarative memories stored
neocortex
where are declarative initially encoded
medial temporal lobe : hippocampus
what are medial temporal lobes important for in declarative memory
consolidation and storage
how did they demonstrate that medial temporal lobes are important in declarative memories
electrical stimulation in temporal lobe
neural recordings from the temporal lobe
amnesia due to temporal lobe damage
what did wilder penfield found
montreal neurological institue (MNI)
what did wilder penfield do
treat patients with severe epilepsy
stimulated brain of awake patients with electrical probes under local anesthesia and observed their responses
i can smell burnt toast
what did wilder penfield contribute to neuroscience
map of motor and sensory homunculus
discovered punctate declarative memories in temporal lobes (ppl described hallucinations or recollections of past experiences)
what brain damage did henry molaison suffer from
removal of temporal lobes to cure seizures
what were the consequences of the lobotomy on HM
no effect on perception, intelligence and personality
anterograde amnesia, cant perform basic human activities
partial retrograde amnesia
impaired declarative memory
good procedural memory
could HM perform the mirror drawing challenge
yes (procedural memory)
why was is hard to recreate the deficits of HM in animals
they could still learn mazes
what test showed deficits similar to HM in animals
delayed matching-to-sample and delayed non-matching to sample (DNMS) in macaques
recognition memory task
shown A, then A and new B, rewarded for either choosing the same or new stimulus
what brain structures seem important in memory deficits seen in DNMS
hippocampus and rhinal cortex
what is the Koraskoff’s syndrome
confusion, confabulations, severe memory impairment, apathy
what are the causes of Korsakoff’s syndrome
chronic alcoholism, thiamin/vitamin B deficiency
Korsakoff’s syndrome is due to lesions is what area in the brain
dorsomedial thalamus and mammillary bodies
who had the Korsakoff’s syndrome and what happened
Jimmie G, 49
intelligence and childhood, adolescence memory intact
severe retrograde and anterograde amnesia
blunted feelings but forget the reason for the emotion
stuck in a single moment of living
T.F. memory formation, retention, retrieval involve a system of interconnected brain areas
T
what are the roles of the hippocampus
binds sensory information for memory consolidation
spatial memory, location of objects of behavioral importance
storage of memories for some length of time
hippocampal lesions affect performance of what task
radial arm maze, cant get food from baited arms
morris water maze, learning the location of the platform
what are place cells
in hippocampus
fire when animal is in or thinks its in a specific place
dynamic, alter place fields based on behavioral needs
T.F. place cells are confirmed in humans
F
PET imaging shows hippocampal activity to spatial navigation of a virtual town
what are grid cells
entorhinal cortex
respond when animal is at multiple locations that form a hexagonal grid
how the brain computes space
T.F. grid cells are confirmed in humans
T in entorhinal cortex
place cells and grid cells suggest the brain region is specialized in
spatial navigation
entorhinal cortex sends info to hippocampus and could help form place cells
what did HMs case bring light to about storage
not all hippocampal memory resides in hippocampus
could run out of space?
HM could remember war and childhood
what is consolidation
process by which long-term memories are formed
which (STM or LTM) requires local synaptic changes and which requires more permanent structural changes
STM = local
LTM = permanent structural changes (growth of existing and new synapses)
what can consolidation be disrupted by
several amnestic treatments
electro convulsive shock (ECS)
beta-blockers (propanolol)
protein synthesis inhibitors (anisomycin)
what are the questions that arise about consolidation
- if u block formation/expression of STM, can LTM still develop
- can u create a LTM in the absence of STM
are STM and LTM separate or connected processes
separate parallel processes
a strong learning event triggers 2 molecular cascades:
1. rapid and short-lasting
2. slow and long-lasting
what is cellular consolidation
strengthening of connections that form LTM initially occur in the hippocampus
what is systems consolidation
with time and rehearsal, changes and memory move out of hippocampus and into cortical structures (hypothesis)
distinction is sometimes made btw _______ and _______ long-term memories
recent ; remote
what are the 2 meanings for consolidation
- recalling a memory initially requires hippocampus
- after systems consolidation, recall of a memory may be hippocampus-independent
how do the two meanings of consolidation explain a pattern of amnesia
explains pattern of retrograde amnesia after hippocampal damage: new memories need hippocampus, older consolidated memories dont need hippocampus
what plays an important role in updating and strengthening consolidated memories
recall, re-use, rehearsal
what is reconsolidation
act of recall that can lead to additional consolidation
why is eyewitness testimony not so reliable
memory reactivation can add false information
what happens if the re-consolidation process is blocked
recall-dependent loss of memory = amnesia
what happens if amnesic treatment after reactivation of a memory
disrupt memory reconsolidation
- weaken or erase memory
- amnesic treatments can be used in humans (propanolol)
what are possible therapeutic applications of reconsolidation blocking
PTSD
cue-induced drug craving and relapse
what does propanolol do
attenuate the emotional content rather than erase the memory itself
what are the most recent studies on reconsolidation
disrupt the reconsolidation and reactivation with extinction
reactivate consolidated memories, followed by extinction training to modify memory
what are the results on fear conditioning followed by reactivation with extinction
no spontaneous recovery when extinction was in consolidation time
spontaneous recovery for when extinction is 6hrs after
possible long-lasting effects specific to priming CS
