Cognition wk 5 Flashcards
availability vs accessibility of memory
what are they
which counts as true forgetting
availability = is it still in the memory store?
accessibility = is it accessible for retrieval
both denote forgetting
Factors that Discourage forgetting
- Better learning at the beginning
- Repeated attempts to retrieve (testing effect/generation effect)
- Effect of testing personal memories (Lenton 1975).
found that even one single test of a memory in 5 years is enough to reduce dramatic decline of no testing.
Jost’s law
When all else is equal, older memories are more durable and forgotten less rapidly than newer memories.
new memories are initially more vulnerable to disruption/distortion until they are consolidated
Do we forget at a constant rate over time?
Who studied this
Ebbinghaus studied his own memory and discovered the Forgetting curve.
- the curve has a logarithmic relationship. (not a constant rate).
- Forgetting rapid initially
- Less additional forgetting at longer intervals
superior autobiographical memory
- uncontrollable remembering
- feels like they relive the events
- remembering is automatic and effortless
- can’t forget unpleasant memories
- memories can be distracting
Forgetting rate
Ebbinghaus found
- forgetting increases as time progresses, but rate of forgetting is different.
There was a forgetting curve.
- logarithmic rel between time and forgetting
- Forgetting rapid initially
- less additional forgetting at longer intervals
experimental evidence for forgetting curve
- forgetting of public events follows principles
- Bahrick highschool grad study. recognition + match ups remained in tact. BUT recall name from picture cue was similar to Ebbinghaus curve
- Forgetting knowlege. foreign language model. rapid forgetting, then levels out after 2 years. same for both good and poor knowledge.
consolidation vs reconsolidation
process that transforms new memories from a fragile state (can be disrupted) to a permanent state
reconsolidation:
process by which a reconsolidated memory restabilizes again after being reactivated by reminders
causes of incidental forgetting
- Trace decay- memories weaken due to passage of time
- Context shifts- diff cues available now than encoding
- Interference- similar memories hinder retrieval
trace decay
memories gradually decay due to passage of time
Priming and familiarity especially prone to decay
How does decay affect memories?
either
- a memories associations fade while memory remains intact
OR - memory itelf and its elements degrade along with its activity level
Trace decay: biological basis
2 expl
synaptic neurons degrade and neurones die as time passes by. memories may fade in same way.
ALSO
the Opposite biological mechanism may explain decay (Frankland et al., 2013).
= Neurogenesis (growth of neurons - especially in hippocampus) means that structure is remodelled and its connections gradually modified. (happens at expense of already stored memories).
- Good fir new learning :)
- Bad for older memories retained in hippocampus
why is it behaviourally so difficult to measure trace decay
2 factors that can’t be controlled
- rehearsal
- Interference from new experiences
correlate of time:
Contextual fluctuation
how similar encoding context is to retrieval context.
incidental context differs more between retrieval and encoding over time
incidental context is less similar to remote paste than recent past
correlate of time
interference
- similar memories accumulate more over time
- whenever the cue that can be used to access a memory becomes associated with other memories
Competition Assumption of interference
Memories associated to a shared cue
automatically impede retrieval when the cue is presented.
▪ A cue activates all associates (more or less).
▪ The activated associates compete for access to consciousness.
▪ Competitors hinder access to target memory.
▪ Interference occurs due to the negative effect of having competitors.
▪ It increases with the number of competitors a target memory has.
part-set cueing example
tendancy of recall to be impaired by the provision of retrieval cues drawn from the same category of items in memory.
providing similar cues strengthens their association to the cue.
competition for non - cues increases + memory worsens.
impairment may be more severe with increased number of cues
e.g. looking for colleagues name, someone tries helping by saying Gary, Bob, Ted
these extra cues are part-set cues
part set cues are strengthened, thus weakening target memory
Retrieval induced forgetting
Selective/partial retrieval can harm recall of other
memories related to the retrieved item
▪ Compared to baseline items for which no related items had
been retrieved
▪ Selective retrieval may contribute to more severe forgetting
for information that is not practiced/retrieved
RIF (retrieval induced forgetting) implications
- retrieval is beneficial
BUT
selective strenghtning may lead to diminished benefits as it causes forgetting of other related things
2 possible mechanisms of interference
Associative blocking: cue elicits a stronger competitor, so cue fails to elicit target trace.
Associative unlearning: associative bond linking a stimulus to a memory trace is punished by weakening it after being retrieved in error.
e.g. want to retrieve A but retrieve X. so X is punished and unlearned.
however, difficult to demonstrate empirically
Functional account of forgetting
- we forget in order to deminish competition in our mind.
- things we rehearse less often we don’t need in our mind.
- facilitates daily functioning, serves our goal directed behaviour and decision making thinking
promotes flexibility, increases cognitive efficiency
