FORGETTING

Problems with Retrieval (Forgetting)  Availability of memory refers to whether the material is actually there to be retrieved  Accessibility of memory refers to the problems involved in retrieving available information  “Grey area” – an area of ambiguity between these two concepts since we can never be 100% sure that what we have forgotten is unavailable  Availability of memory refers to whether the material is actually there to be retrieved  Accessibility of memory refers to the problems involved in retrieving available information  “Grey area” – an area of ambiguity between these two concepts since we can never be 100% sure that what we have forgotten is unavailable

Tulving & Pearlstone (1966)  They read participants lists of varying number of words (12, 24 and 48) consisting of categories (eg. Animals) of one, two or four examples per list, plus the category name  Participants were instructed to try to remember only the examples  Half the participants (Group 2) free-recalled the words and wrote them down on blank pieces of paper  The other half (Group 1) was given the category names on the paper  Group 1 recalled more words, especially in the 48 item list when compared to group 2  When Group 2 was given the category names, recall improved  His illustrates very well the availability/accessibility distinction  The category name acted as a contextual cue, helping to make accessible what was available  Group 2 participants knew  They read participants lists of varying number of words (12, 24 and 48) consisting of categories (eg. Animals) of one, two or four examples per list, plus the category name  Participants were instructed to try to remember only the examples  Half the participants (Group 2) free-recalled the words and wrote them down on blank pieces of paper  The other half (Group 1) was given the category names on the paper  Group 1 recalled more words, especially in the 48 item list when compared to group 2  When Group 2 was given the category names, recall improved  His illustrates very well the availability/accessibility distinction  The category name acted as a contextual cue, helping to make accessible what was available  Group 2 participants knew

Four ways of forgetting 3) Failure to store -Does not reach LTM -Encoding Failures 4) Motivated Forgetting -Supression -Represion 1)Retrieval failure - Decay theory - Rehearsal 2) Interference -Proactive interference -Retroactive interference

It’s on the tip of my tongue (Brown & McNeill, 1966)  Brown and McNeill gave participants dictionary definitions on unfamiliar words and asked them to provide the words themselves  Most participants either knew the word or knew that they didn't know it  Some, however were sure they knew the word but couldn't recall it (it was on the tip of their tongue)  About half could give the word’s first letter and the number of syllables, and often offered words which sounded like the word or had a similar meaning.  This suggest that the required words were in memory, but the absence of a correct retrieval cue prevented them from being recalled  Brown and McNeill gave participants dictionary definitions on unfamiliar words and asked them to provide the words themselves  Most participants either knew the word or knew that they didn't know it  Some, however were sure they knew the word but couldn't recall it (it was on the tip of their tongue)  About half could give the word’s first letter and the number of syllables, and often offered words which sounded like the word or had a similar meaning.  This suggest that the required words were in memory, but the absence of a correct retrieval cue prevented them from being recalled

Forgetting in short–term memory  Trace Decay Theory - Focuses on explaining STM forgetting in terms of its limited duration  *Pure trace decay is very difficult to test.  Displacement Theory - Focuses on explaining STM forgetting in terms of its limited capacity  Trace Decay Theory - Focuses on explaining STM forgetting in terms of its limited duration  *Pure trace decay is very difficult to test.  Displacement Theory - Focuses on explaining STM forgetting in terms of its limited capacity

Forgetting in Long-Term Memory  Interference Theory  - One explanation of LTM forgetting is that over time more and more material will be stored and become confused together  - Interference is most likely to occur between similar material  -Proactive interference is where material learnt first interferes with material learnt later  - Retroactive interference is where material learnt at a later time interferes with material learnt earlier  Interference Theory  - One explanation of LTM forgetting is that over time more and more material will be stored and become confused together  - Interference is most likely to occur between similar material  -Proactive interference is where material learnt first interferes with material learnt later  - Retroactive interference is where material learnt at a later time interferes with material learnt earlier

The Role of Emotion in Forgetting  Repression  - Forgetting is motivated by the desire to avoid displeasure, so embarrassing, unpleasant or anxiety-producing experiences are repressed – pushed down in to the unconscious  Flashbulb Memory  - Brown and Kulik (1977) suggested some events can be remembered in almost photographic detail – as if they are imprinted upon the mind.  Repression  - Forgetting is motivated by the desire to avoid displeasure, so embarrassing, unpleasant or anxiety-producing experiences are repressed – pushed down in to the unconscious  Flashbulb Memory  - Brown and Kulik (1977) suggested some events can be remembered in almost photographic detail – as if they are imprinted upon the mind.

H.M. (Milner et al. 1968)  H.M. (Milner et al. 1968)  - H.M. is probably the single most studied amnesic patient in the history of neuropsychology (Rose 2003)  - He’d been suffering epileptic fits of devastating frequency since the age of 16  - In 1953 (aged 27) he underwent surgery aimed at alleviating his epilepsy  - The anterior two-thirds of his hippocampus and amygdale plus part of the temporal lobe (both sides of his brain) were removed   H.M. (Milner et al. 1968)  - H.M. is probably the single most studied amnesic patient in the history of neuropsychology (Rose 2003)  - He’d been suffering epileptic fits of devastating frequency since the age of 16  - In 1953 (aged 27) he underwent surgery aimed at alleviating his epilepsy  - The anterior two-thirds of his hippocampus and amygdale plus part of the temporal lobe (both sides of his brain) were removed 

H.M. Cont.  - His surgery was fairly successful but at that time, the role of these brain structures in memory was unknown, and he was left with severe anterograde amnesia that is he has near normal memory of anything learned before the surgery, but severe memory defects for event that occurred afterwards  - His Short Term Memory is generally normal but cannot transfer into Long Term Memory or, if he can, is unable to retrieve it.  - He has almost no knowledge of current affairs, because he forgot all the news as soon as he’s read about it  - He has no idea of the time unless he looks at the clock  - He cannot remember that his father has died, or that his family has moved house, and he rereads the same magazine without realising he’s already read it  - People he met after the operation remain, in effect, total strangers to him and he has to “get to know them” afresh each time they meet  - He’s able to learn and remember perceptual and motor skills, although he has to be reminded each day just what skills he has.  - His surgery was fairly successful but at that time, the role of these brain structures in memory was unknown, and he was left with severe anterograde amnesia that is he has near normal memory of anything learned before the surgery, but severe memory defects for event that occurred afterwards  - His Short Term Memory is generally normal but cannot transfer into Long Term Memory or, if he can, is unable to retrieve it.  - He has almost no knowledge of current affairs, because he forgot all the news as soon as he’s read about it  - He has no idea of the time unless he looks at the clock  - He cannot remember that his father has died, or that his family has moved house, and he rereads the same magazine without realising he’s already read it  - People he met after the operation remain, in effect, total strangers to him and he has to “get to know them” afresh each time they meet  - He’s able to learn and remember perceptual and motor skills, although he has to be reminded each day just what skills he has.