long-term memory (lecture 2 & 3 verde) Flashcards
what is consolidation?
an ongoing process
-connections at the synaptic & structural level
what is reorganisation?
initial dependence on hippocampus & medial temporal lobe -> to more permanent representations in neocortical areas
what happens in the process of consolidation in long term memory?
new memory representations initially formed by the hippocampus but over time become consolidated in other regions of the cortex.
what treatment can negatively impact long term memory?
-electroconvulsive therapy can produce memory problems in humans - short term and long term amnesia
what is retrograde amnesia?
-Loss of memories prior to the onset of amnesia
what did Squire et al 1975 test?
Patients undergoing ECT had memory tested before and immediately after series of 5 ECT treatments.
Test: recognise names of
television shows that ran
for exactly 1 year over
period of two decades.
Memory deficit only
for last 3 years.
what are two components of memory loss?
-anterograde: no new memories post-trauma
-retrograde: loss of pre-trauma memories
what does retrograde memory loss show?
a temporal gradient -> remote memories are intact but memory loss increase closer in time to trauma
what did Squire et al 1989 study?
retrograde amnesia
-Amnesics in their 50s (and matched controls):
- Questions about public events from 1950s-1980s
- Identify photos of famous people 1940s-1980s
what did squire et al 1989 find?
-Memories consolidate over time: Newer memories are more fragile and susceptible to disruption.
-Temporal gradient of memory loss: Worse closer to trauma.
what did Brown 2002 do?
conducted a meta analysis of studies on retrograde amnesia
-results were: absolute = actual recall,relative = recall as % of control group recall
-Memories consolidate over time: Newer memories are more fragile and susceptible to disruption.
what happens during consolidation in long term memory?
transfer to cortical representations increases stability of memories
- reactivation strengthens neuronal connections and creates additional copies (more resistant to loss)
This can continue for years.
why are things easy or hard to remember?
-grandmother cell -> memory is stored in the particular neuron for your grandmother (penfield, 1940a-50s)
-distributed pattern of activation
-retreiving one memory among many memories
what effects encoding?
-quality of representation
-depth of processing
what effects quality of representation?
-imagery/richness
-distinctiveness
what did Shepard 1967 study?
612 colour pictures
Recognition memory accuracy (% correct):
2 hours = 99.7%, 7 days = 87%, 4 months = 57.7%
what did Standing 1973 study?
1,000 & 10,000 photographs tested after 2 day delay.
Normal photos (dog)
Vivid photos (dog with pipe in mouth)
Recognition memory accuracy (% correct):
1000 vivid photos = 95.2%
1000 normal photos= 90.8%
10000 normal photos =72.8%
what is the picture superiority effect?
pictures are more memorable than other stimuli, when you see things as pictures you will remember them better than words
What did Kimble 1976 study?
what did Bower & Winzenz 1970 study?
ppts studied word pairs: either repeat silently or form mental image.
imagery lead to superior memory -> richer memory as more parts to the picture to remember
what are autobiographical memories?
“mental time travel” or reliving the past highly associated with mental imagery.
what is aphantansia?
(poor or no mental imagery ability) associated with reduced autobiographical memories
what did Macleod et al 2010 study?
the production effect
-Study list of words: read silently or say aloud
● Better recognition memory for “produced” words
what did Ozubko et al 2012 study?
production effect seen with sentences & texts
(e.g., more naturalistic materials)
● memory advantages even after 1 week
Similar to memory advantage for pictures…
what are properties of disctinctivness that may effect quality of representation?
intrinsic properties
unusual
emotional
arousing
what is the isolation effect of distinctiveness?
relative distinctiveness = increased processing or attention
what did Van restorff 1933 find?
what did craik & tucking 1975 find?
gave ppts study word and answer question
asked ppts: Is the word in capital letters? (structural),Does the word rhyme with X?(phonemic),
Would the word fit in the sentence (semantic)
Conditions ->Low to High depth of processing
what is the self-reference effect?
an especially effective deep type of processing
deeper = more personally meaningful
what did Nairne et al 2007 research?
ppts learned word lists.
Rated relevance for:
Survival, Moving, Pleasantness
do we see the opposite of the temporal gradient?
-psychogenic amnesia, psychological factors instead of biological.
what is a problem of retrieval?
-how to retrieve one memory among many?
what does encoding specificity mean?
to get info in memory must reinstate the conditions at encoding
-memory is better if the retrieval context matches the encoding context
how is recall affected when the same cue is used at encoding & retrieval?
tulving & Thompson 1970
-Study cue-target pairs
HOT – COLD (strong associate)
or SNOW – COLD (weak associate)
-Later, give cue as “clue” to remember target.
Expected: Strong associate = better retrieval cue
what are forms of encoding specificity?
-transfer appropriate processing
-state-dependent learning
what is research into transfer appropriate processing?
Memory best when use the same
processing at encoding and retrieval
Morris, Bransford, and Franks (1977)
Encoding conditions:
Semantic (does target word fit sentence?)
“the book was on the shelf.”
Rhyme (does the target word rhyme?)
“spear rhymes with fear.”
test conditions: standard recognition and depth of processing prediction.
what did Godden & Baddeley 1975 find?
memory best when environmental or mental context same at encoding and retrieval
what are conclusions of studies on state dependent learning?
Memory better when mental or environmental context same at encoding & retrieval
what are factors of memory?
encoding, consolidation and retrieval
how are episodic memories encoded?
Familiarity feeling of recognition without specific details (fast, automatic)
Recollection recall of specific
episodic details or associations (slow, deliberate, conscious)
based of studies of: subjective experience, effect of attention, time course of retrieval.
what Is subjective experience?
Ask people whether they “remember” or “know” they’ve encountered something before.
what did Gardiner et al 2000 study?
People studied word list, later described subjective feelings during recognition test
Label feelings: “Remember” “Know” “Guess”
… that word was in the studied list.
what did Gardiner & Richardson-Klavehn 2000 find?
Objectively, “Remembering”:
* associated with accurate memory for source, context, associations
* declines rapidly over time
* large impact of reduced attention
Problem with studying subjective experience:
* people not always consistent in how they use terms like “Remember” and “Know”
- subjective states may not directly measure
underlying memory processes
what did research into attention find?
Jacoby, Woloshyn & Kelley, (1989)
People saw list of famous & non-famous names under full or divided attention (detect digits in auditory stream).
Famous = survey: 60-70% recognise as famous
but not so famous that most could recall
the achievement that led to fame.
Later made Fame or Recognition Memory judgments.
Fame judgments likely based on familiarity, not recollection.
Recognition Memory based on familiarity & recollection.
what are conclusions from Jacoby et al 1989?
Divided attention at encoding large effect on recognition memory but no effect on fame judgments.
Fame judgments = familiarity
Recognition memory = recollection + familiarity
Recollection requires conscious attention
Familiarity automatic, unconscious
who researched into time course of retrieval?
Jacoby, Jones & Dolan, (1998)
Study two word lists: List 1 (Saw) & List 2 (Heard)
Memory test (source discrimination):
say “yes” only to Heard words
Source judgments = recollection
(familiarity is not useful)
- If recollection takes more time, poor source discrimination when judgments made quickly (response deadline).
- If familiarity is fast, quick judgments based on familiarity.
what are results of Jacoby, Jones & Dolan (1998)?
how does contribution of recollection and familiarity change over time?
Initial reliance on familiarity until recollection becomes available later in time.
what may people prefer to rely on?
recollection -> more accurate and less ambiguous
- can counteract false familiarity
-When conscious attention or time is limited (at encoding or retrieval), judgments based more on familiarity, less on recollection
summarise the lecture topics
memory consolidation: temporal gradient in retrograde amnesia
memory encoding: imagery/richness & distinctiveness
memory retrieval: encoding specificity
episodic memory: familiarity & recollection, subjective experience, attention, time course
what is the serial position curve?
In free recall, more items are recalled from start of list
(primacy effect) and end of the list (recency effect).
First items recalled tend to be from end of study list
Recency Effect: Items still in STM
Primacy Effect: Longest rehearsal = more likely to be successfully stored in LTM
what do selective STM deficit lead to?
speech and language impairment
what did Warrington & Shallice 1969 do?
case study on KF
-impaired STM (digits span)and preserved LTM (paired-associated learning)
what did Shallice & Warrington 1970 find?
tested KF with immediate free recall of 10-word list
-KF shows recency effect for only the last word -> evidence of reduced STM span
what did Warrington et al 1971 find?
case study of three patients: KF, JB, WH
immediate free recall of 10 word lis
-found 30 sec delay reduces recency effect but only on the last word
what is amnesia caused by?
damage to the medial temporal lobe and hippocampus, from trauma
what are the two components of memory loss in amnesia?
-retrograde: loss of pre-trauma memories
-anterograde: no new memories post-trauma
what functions are preserved in amnesiacs?
-knowledge of language: can communicate and understand normally
-sufficient memory to keep track of what is being said within a conversation
-no deficit in STM, digit span and IQ
what did Warrington & Weiskrantz 1970?
-amnesiac worse than controls on memory tests like recall and recognition
what did Cohen & Squire 1980 find?
Word pair learning for various types of amnesiacs
what did Milner et al 1968 find?
-dissociation between STM and LTM is evidence of different memory systems
how does a person with damaged STM store information in LTM?
information can be stored in LTM without passing through STM
-STM deficit is an inability to manipulate or use, rather than inability to store, information in working memory.
what does Cowan 1999 propose for an alternative conception?
-working memory is just an activated area of LTM under the current focus of attention
-STM deficit is a problem of the central executives ability to focus attention in LTM
-some forms of long-term memory are intact in amnesia.
what are the two types of memory?
-declarative
-procedural
what is declarative memory?
-conscious memory
what is procedural memory?
-perceptual-motor learning
how is LTM intact in amnesiacs?
-amnesiacs show perceptual priming
-amnesiacs show fewer errors on second indentification test
what did Cohen & Squire 1980 find?
trained amnesiac patients in reading backward -image words
-non of the amnesiacs reported that words had been repeated, but all the non-amnesiac controls reported this.
what did Milner et al 1968 do?
gave patient HM a tactile maze to learn
-placed his hand on start, then moved to finish then started again
-maze had 5 decision points
-30 training sessions, 10 trials each over 10 days.
-As the trials went on HM made less errors and improved in accuracy.
-he remembered task procedures but not how we learned them
what are implicit tests of memory?
fragment identification
word-stem completion
what are explicit tests of memory?
free recall
cued recall
recognition
what did Warrington & Weiskrrantz 1970 do?
Amnesic worse than controls on explicit memory tests like recall and recognition.
Amnesics equal to controls on implicit memory tests like word fragment identification and word stem completion.
what method should be used for declarative memory?
explicit
what should test non declarative memory?
implicit
true of false:Amnesics are impaired in declarative memory tasks but perform normally in non-declarative memory tasks.
true
can amnesics learn real skills?
Amnesic MT trained to find her way around rehabilitation unit (Brooks et al., 1999)
- No accurate explicit memory, preserved implicit & procedural learning
what did Brooks et al 1999 do?
8 weeks of daily training on routes like:
* Bedroom to Dining Room
* Bedroom to Gym
Incremental learning in real and virtual environments:
move short distance from destination, then slightly farther distance, etc.
After learning, could still find route weeks later.
BUT did not know that she knew the route
how are memories consolidated in long term memory?
Memories initially fragile and easily disrupted. Become consolidated (stronger) over time
-Pinel (1969)
Rats learned spatial location then given electroconvulsive shocks.
what is consolidation?
strengthening of synapses and systems to consolidate
-hippocampus plays role in consolidation
-time helps with consolidation (Muller & Pilzecker, 1900)
-sleep helps (Gais, Lucas, born, 2006) as protects learning from interference and promotes consolidation -> slow wave sleep, neuronal patterns formed during learning are reactivated & strengthened
what did Muller & Pilzecker 1900 do?
Learned 2 word lists (List 1, List 2)
No delay or delay between Lists
● Recall of List 1 much
better after delay
● Memory initially fragile
and easy to disrupt by
learning List 2
● Delay allows consolidation
of List 1 memory
what did Gais,Lucas,Born 2006 study?
had a time interval constant
sleep deprivation lead t increased forgetting
-> sleep helps consolidation and protects learning
-sleeping soon after learning helps consolidation and protects learning
what is reorganisation?
initial dependence on hippocampus & medial temporal lobe ->to more permanent representations in neocortical areas
