Lecture 7- Consolidation and forgetting Flashcards
what is forgetting
we get lots of material
not a failure to encode this material as it as never internalised
one must have formed a memory in order to forget it
forgetting is the inability to recall somethingnow that could have been recalled earlier on occasion
define forgetting in reference to inaccessibility
sometimes we need a cue in order to recall that memory - in absence of that cue we have an issue with inaccessibility
we cant disprove the inaccessibility account of forgetting
- therefore when discussing forgetting we don’t dissociate unavailable / lost memories and inaccessible ones
what is the curve called hich is also known as the curve of forgettig
ebbinghaus curve of forgetting
- nonsense syllable experiment
what was the method in ebbinghaus study
Over the course of days, he kept relearning lists of nonsense syllables (e.g., RUR, HAL, BEIS, etc.)
Forgetting was measured as percent savings (a comparison of immediate testing versus testing after a delay)
Information is rapidly forgotten at first (non-linear)
what are the 4 explanations of forgetting and explain
Trace decay
Memories just fade over time
Interference
Memories (particularly if similar) get confused
Cue-dependent forgetting
Issue of accessibility and not availability
Consolidation
New memories are fragile
they are not mutually exclusive
what is trace decay
memories fade over time
what is a practical example of trace decay
Model of working memory: the phonological loop (Baddeley & Hitch, 1974)
Without rehearsal the phonological information fades from the store
( decay of phonological loop- but if keep rehearsing will store )
Word Length Effect (Baddeley et al., 1975)
More time elapses for longer words before rehearsal
Therefore longer words should be forgot to a greater extent …
what is the Word Length Effect (Baddeley et al., 1975) for trace decay
Word Length Effect (Baddeley et al., 1975)
More time elapses for longer words before rehearsal
Therefore longer words should be forgot to a greater extent …
eg if phon loop = 9 seconds, takes longer to fit in longer words than shorter words to be able to remember
what are the common problems with trace decay
Brown-Peterson (1958)
Subjects presented with 3-consonant trigrams (BDK)
Required to count backwards by threes
0-sec delay: 90% correct recall
18-sec delay: 7% recall
Retention duration ~20 sec
- shows average of the trials = more forgetting and the forgetting rate of the first trial indicates less forgetting - all additional trials show INTERFERENCE with forgetting
- sleeping
info lost at same rate when sleeping or not sleeping
but sleeping has less decay - so isnt only area of importance
what is interference
our ability to remeber current information is disrupted by previous and future learning
- effects not simply due to passage of time
- more similar memories = more confusion
what are the two types of interference
Proactive
Old information interferes with learning new information
Waiter: first order of a shift interferes with memory of last order
Retroactive
New information interferes with retention of old information
Waiter: last order of a shift interferes with memory of first order
what is the evidence for Retrieval interferance
- Waugh and Norman probe digit task View 16 digits and last digit tells you which to report 1596234789024815 -> 9 1596234789024817 -> 8 1596234789024812 -> 4
Performance was the same with one number per second and 4 numbers per second.
Decay account should have resulted in poorer performance for the slower 1 per second condition.
Wickens 1976
- pps listen to 3 words counted backwards for 15 seconds then recalled words
- 4 trials- diff words on each trial
- words Words from a new category caused a release from PI
what are the problems with interferance
Does not explain why rate of forgetting (Ebbinghaus) slows over time
As even more interference should result in accelerated forgetting
Overlap with other accounts
Time-based decay
Cue-dependency
what can cue dependant forgetting be likened to
The Search-Engine Analogy
Searching for a specific item online
The web-page exists somewhere but in order to find it you need the right search-term (or cue)
what is cue dependant forgetting
Cue dependent forgetting = failure to retrieve as the appropriate cue has not been presented
Memory exists but issues in accessing that memory
explain meeter 2005 assessment on cue dependant forgetting
Meeter et al. (2005) examined the forgetting curve for newsworthy events
Performance was better for multiple choice questions (52%) compared to free recall (31%)
The MCQ answer options operated as a cue
Forgetting why you entered a room
Must go back to where you were in order to remember (back to where the cues are)
explain tulving and perstones 1996 assessment on cue dependant forgetting
Tulving and Pearlstone (1966) found that participants recalled twice as many words when given a cue compared to free recall
Memory exists but requires the appropriate cue
But performance not at 100% so other explanations needed?
Or perhaps the appropriate cue has not yet been presented
what are the weaknesses of cue dependent forgetting
- not falsifiable
performance isnt 100% with cues
why is the context important in cue dependent forgetting
Memory is better when the context at learning and retrieval is the same
Context operates as a cue to recall
