Chapter 9 Incidental Forgetting Flashcards
Incidental forgetting
Without intention to forget
Hyperthymestic syndrome
Uncontrollable remembering
No special ability to remember arbitrary info
Over time
Forgetting slows down logarithmically
Meeter
Question respondents about events sufficiently noteworthy to attract attn of people at time they happened
Ask about headlines
Ppl’s recall for events dropped 60 to 30% in a year
Recall worse than recognition
Bahrick
Ability to recognize face remains
Ability to recall name for face worse
Bahrick
Foreign language forgetting levels out after 2 years with little further loss
Memory traces freeze ‘permastore’
Overall retention is determined by level of initial learning
Recall vs recog
Recall forgets faster
Tulving
Distinction between availability and accessibility
Inaccessibility considered forgetting
Jost’s Law
If two memories are equally strong at a given time, the older will be forgotten less rapidly
Consolidation
A new trace is gradually woven into the fabric of memory and by which its components and their interconnections are cemented together
Caused by neural structural changes in synaptic connections
Systemic consolidation is that hippocampal storage and retrieval diminishes until cortex retrieves memory on its own
Hippo recurrently reactivates brain areas involved in initial experience until these areas are interlinked in way that recreates initial memory
Vulnerable to disruption until reaches independence
Each time a trace is reactivated in memory (reminder exposure) it has to restabilize because it’s vulnerable
Consolidated memories are disruptable by drugs, shocks and must reconsolidate
Retrieval’s effect on forgetting
Linton
Recalled randomly selected events from diary
What effect did earlier recalls have on later memorability of event?
Item not retested forgotten, retested less forgotten
Factors Encouraging incidental forgetting
Trace decay: memories weaken over time, affecting verbal and visual WM
Activation decays gradually even it item remains stored - recent exposure to word helmet may activate pre-existing concept
Associations between features themselves deteriorate via degradation over time by neural degradation
Frankland
Memory decay encourages new neuron growth neurogenesis
Good for new things, bad for retention of existing memories
Infantile amnesia
Demonstrating decay in the absence of other activities such as storage of new experiences or rehearsal hard - the person would need to be kept in a mental vacuum, w no rehearsal, thoughts, experiences to contaminate memory, plus is trace unavailable or just inaccessible?
Correlates of time
These provide alt explanations but don’t disprove decay
Number and quality of cues - relevance changes - world changes - contextual fluctuation
Delaney: word list, daydreaming about vacation, second word list, test of first list. Daydreaming remembered fewer words from first list - further abroad correlated with how much
Interference: similar memories - routine less memorable than unique
Arises when cue used to access target becomes associated to additional memories
Those items compete with target for access to awareness - competition assumption - they fight - ‘competitors’
Supported by tendency for recall to decrease with number of item paired with same cue - ‘cue-overload principle’
Need not be full episodes
Retroactive interference
Forgetting caused by encoding new traces into memory in between the initial encoding of target and when it is tested. Storing new experiences impairs ability to recall older ones
Cue words in first list often repeat in second with new paired word. Testing by giving first word of each pair and asking response from first list
Second list impairs recall from first; more training on second list increases retention of first list
Little retroactive interference when pairs on two lists unrelated, thus not every type of intervening experience impairs memory
Rugby players: time unimportant, number of intervening games critical. Indicating forgetting due to interference not trace decay
Proactive interference
Older memories interfering with retrieval of more recent
Old password
Underwood: naive students remembered lots, students with 20 trials remembered less
Paradigm tests list 2
People more likely to forget list 2 after studying list 1
Part-set cuing impairment
Cues drawn from same category of items in memory
Mueller
Slamecka: Given cues from members of each category to help recall remainder
Surprise! Cues didn’t help recall noncue items, ppl receiving cues performed worse than no cues
Cues increase competition consistent
Bauml: part-set restudy group didn’t forget noncue items, whereas curing and retrieval groups did - reexposure strengthened the recall of the four items across conditions. Strengthening doesn’t induce forgetting
Collaborative inhibition
When people get together to remember material that they each learned, they remember less than they would separately
works on part-set cuing
Retrieval-induced forgetting
Anderson
Retrieval practice enhances recall of practiced items but impairs related items
People study categories and retrieve examples using cues, but unpracticed examples bad
Omitting material from study hastens forgetting
Similar effects on short answer but not MC exams
Interrogating people about stolen items impares memory for related items
After discussing pirate events with kids, kids recalled nondiscussed elements less well than control group of children on last day
With others
Retrieval-induced forgetting
We recall events along with person doing the recounting and subject ourselves to retrieval-induced forgetting for whatever the speaker doesn’t say
Society’s collective memory
Response competition theory
McGeoch
Memories compete for access to awareness when their shared cue is provided
People forget first-list responses because cues used to access them now elicit second-list responses
Anderson: strength-dependent competition
With each accidental retrieval, the wrong answer grows stronger
People forget unpracticed exemplars of practiced categories because associations to the practiced memories dominate retrieval
You can’t remember dinner 4 months ago because retrieval brings recent dinners
Unlearning hypothesis of retro interference
Melton
Assoc between stimulus and trace weakens when trace is retrieved inappropriately
Wrong password punished, decreasing chances of popping up in future
Unlearning and blocking compatible but proof of unlearning hard to establish
Forgetting by inhibition
Putting a stop to remembering
to stop old phone number from recall
Remain available
Retrieval-induced forgetting cue dependent
If you switch to another cue like monkey, this circumvents fruit-orange and fruit-banana and releases banana for retrieval
Inhibition hypothesis: need to overcome interference during retrieval triggers inhibition. If so, active retrieval on practiced items should be necessary to induce forgetting of competitors. Replacing retrieval practice trials with restudying fruit-orange should eliminate leter forgetting of competitors - resolves interference from banana
Retrieval practice impairs retention of unpracticed competitors (banana)
Interference dependence
Tendency for retrieval-induced forgetting to be triggered by interference from competing memory
Anderson
Divided attention
Participants in divided attn condition showed significantly less retrieval induced forgetting than full attn participants
Giving ppl highly stressful task before they performed retrieval practice undid retrieval-induced forgetting
Retrieval-induced forgetting is attn dependent
MRI
Early trials had more activation in LR ventrolateral PRF and anterior cingulate cortex - cog control and resolution of response conflict
By reducing distraction from competing memories, people expend less neural effort during retrieval practice to retrieve the things they wanted to recall
