Memory

Memory

1. Memory processes

   • Encoding
     • Visual
     • Acoustic
     • Semantic
     • Baddeley's study
       • Aim: To see if there was a difference in the type of encoding used for LTM and STM
       • Method: Groups A, B, C, and D were given lists of words and asked to recall them in order after a certain period of time
         • Group A: Acoustically similar list Group B: Acoustically dissimilar list Immediately after being given the list
         • Group C: Semantically similar list Group D: semantically dissimilar list 20 minutes after being given the list
       • Results: A did better than B C did better than D
       • Conclusion: STM is acoustically encoded, LTM semantically encoded
       • Not really teting LTM
         • It is unclear whether 20 minutes is a long enough period of time for it to be considered LTM, so baddeley may still have been testing LTM
       • Artificial task
         • We don't recall lists of words on a daily basis, therefore the experiment lack ecological validity
       • A laboratory experiment
         • Low influence from extraneous variables, meaning the results are high in internal validity
   • Retrieval
     • Recognition
       • identification of something from previous encounters or knowledge.
     • Cued recall
       • remembering something with the help of a signal
     • Free recall
       • Remembering something without the help of any cues
   • Storage
     • Long term memory
       • Episodic
       • Procedural
       • Semantic

2. Structures of memory

   • Multi-store model (MSM)
     • Sensory
       • STM
         • Maintenence rehearsal/loop
           • LTM
             • Semantic coding No accurate known capacity Up to a lifetime
         • Acoustic coding 5-9 items of information 30 seconds
       • High capacity Less than half a second
     • Has supporting evidence (eg: Baddeley/Murdock) which shows that the memory stores are different and separate
     • The model is too simple. Other research shows that STM and LTM are bot split into further sections (eg: STM: acoustic, visual LTM: semantic, procedural)
       • The model is based on artificial materials, which have low ecological validity
   • Primacy and recency
     • Murdock's serial position study
       • Aim: to see if memorisation of words was effected by the number of words that had to be memorised
       • Method: Randomly selected 4000 most common words in English language. Participants listen to 20 word lists with between 10-40 words per list.
       • Results: more words were remembered if they were in the beginning of the list or at the end. Few words were remembered from the middle of the list
       • Conclusion: First few words are remembered more because they were rehearsed and stored in long term. Last few were remembered because they were still in the short term memory store. Middle words were in neither, making them more difficult to remember
       • Lab study
         • High internal validity as extraneous variables were controlled
       • Artificial task
         • Low ecological validity since people don't have to memorise words daily, menaing it is an unrealistic representation of memory

3. Bartlett's theory of Reconstructive memory

   • Memory is stored in fragments and when recalled, the gaps are filled by our own knowledge, resulting in inaccurate memories
     • Knowledge used to fill gaps is affected by social and cultural expectations of what the memory should be
   • Each time a memory is recalled, it is slightly different than it was before
   • "Effort after meaning"
     • we remember by recalling the general meaning of things, and then piece these together to make a big picture afterwards
   • War of the Ghosts study
     • Aim: to investigate how memory is reconstructed when asked to recall over a period of weeks and moths
     • Method: Showed participants a story that was different from their own culture and asked them to recall it after a period of time. The new version is shown to another participant, and so on.
     • Results: Some parts of the story were remembered, others were changed to fit the person's expectations (eg: some phrases like canoe were changed to boats). The story was shortened.
       • Conclusion: the changes were made to make the story easier to remember. They only remembered the meaning of the story, and filled in the rest with their own knowledge
     • Lacks control
       • No set standard for how/where the story was recalled which suggests that Bartlett's conclusion is exaggerated
     • Low ecological validity
       • The story was unusual so it may not reflect everyday memory processes
   • Has real-life applications
     • Can explain the problem of eyewitness testimonies not being as accurate as they once were regarded as
   • some memories are accurate
     • Other studies have shown that memory can be very accurate, so to assume that memory is always inaccurate is wrong.

4. Factors of accuracy

   • Interference
     • McGeoch & McDonald
       • Aim: to see whether a second memory effects the first
       • Method: twelve participants learnt a list of ten words until they could recall them 100% accurately. They were then shown a second list. After that, they were asked to recall the first list
       • Results: When asked to recall the first list of words, participants did worst when the words were similar (synonyms) to the first list. They did best when there was no new list given
       • Conclusion: interference is strongest when the intervening activity is similar.
       • Laboratory experiment
         • used counterbalancing to ensure practice wasn't a variable
       • Artificial task
         • People don't memorise word lists on the daily, so the experiment may not be a true reflection of memory
       • Not really forgetting
         • Interference effects may just be temporary and the information may not be truly forgotten. Participants given a cued recall test in another study are able to recall a lot of the information McGeoch & McDonald said they 'forgot'
   • False memories
     • Reconstructed memories may be completely false
     • Loftus and Pickrell 'Lost in the Mall' study
       • Aim: To see if false memories could be created in participants through suggestion
       • Method: 24 participants between 18-53 yrs old were given 4 stories about their childhood. 3 real, 1 fake. Fake was a realistic story about getting lost in the mall. They read the story and were asked to write anything they recalled of the event. Later, in an interview, they were asked to recall as much as possible on the events
       • Results: 6 participants recalled the false story, picking it as a true story from their childhood
       • Conclusion: imagining an event COULD implant it. Shows that false memories are reducing the accuracy of memory because of reconstructive memory
       • Artificial task
         • Not a true reflection of memory
       • Ethical issues
         • Potentially harmed participants psychologically from the implantation of false memories
       • Real-world applicaiton
         • Changed the way courts handle eyewitness testimonies -- unreliable
   • Context
     • Triggers present during recall can help increase the accuracy of memories
     • Godden and Baddeley's study
       • Aim: Does the environment (context) in which memory is recalled affect the accuracy?
       • Method: 18 participants (divers) were recruited. They had to listen to a list of 36 unrelated words either on the beach or 10 feet underwater
         • Results: Those who tested in the same conditions they memorised them, recalled more
           • Context of learning can act as a cue when recalling information
       • Artificial task
         • Word-learning isn't done everyday, so this experiment is an unrealistic representation of memory
       • Recall was short term
         • Words were recalled almost immediately, so the effect of context may only apply to STM and not LTM