Memory

• Accuracy of EWT: post event discussion


  When a witness to a crime discusses it with another witness. Their eyewitness testimones become contaminated and therefore affects the accuracy of recall.
• Leading questions on EWT study

  METHOD:  45 american students shown 7 films of different car accidents. After each film, pp gave questionire asking them to describe the accident, and also asked a series of specfic questions such as “ how fast was the car going when they _____ each other”. PPs then divided into 5 groups and asked question with different words in the gap.
• FINDINGS of lotus and palmer misleading information study

  Smashed = 40 mph

  Collided = 39 mph

  Bumped = 38 mph

  Hit = 34 mph

  Contacted = 20 mph

  Shows that language can have a distorting effect on EWT
• Goberts post event discussion exp

  GOBERT:

  Lab experiment where paired pps watched a video of the same stimulated robbery from different angles so each pp could see elements in the event that others couldnt. Both pps discussed what they had seen on the video before individually completing a test of recall.

  Another group ddint take part in post event discussion.

  Findings: 70% of pps mistakenly recalled aspects of events they didnt see in video but had picked up in post event discussion. 0% of other group made a mistake
• Jacob’s STM capacity research

  Jacobs: used digit span test. 440 females aged 8-19 from North Lodon Collegete School. PP had to repeat back a string of numbers/ letters in sameorder and number of digits gradually increased until pp could no longer recall. Found students hold an average span of 7.3 letters, supporting notion of 7+/-2 chuncking method
• Petersons STM duration exp

  Peterson and Peterson used a lab exp of 25 psychology students who had to recall trigrams such as TGH/CLS. They were presented one at a time and had to be recalled after intervals of 3,6,9,12,15 seconds. After ppcounted backwards in 3s from a random number until they saw a red light appear.

  Found the longer ecach student had to count, the less able they could recall accurately.
• Baddelys STM/LTM coding exp

  Baddely: Pp given one list of words and asked to recall in correct order

  Group 1- acoustically similar

  Group 2- acoustically disimlar

  Group 3- semantically similar

  Group 4- semantically disimilar

  When recall was immediately after, tended o do worse with acoustically similar words, so STM is coded acoustically

  When recall was after 20 minutes, did worse on semantically similar words, so LTM is semantic
• Capacity of LTM = unlimited

  Capacity of STM = 5-9 pieces

  Capacity of SR = Very large capacity
• Duration of LTM = unlimited

  Duration of STM = 18-30 seconds

  Duration of SR = 1/2 second
• Coding of LTM = semantically

  Coding of STM = acoustically

  Coding of SR = modality specific
• CENTRAL EXECUTIVE

  controls other slave components and decdies whats required for a task.

  Capacity: limited to no storage capacity

  Coding: each sense is different
• PHONOLOGICAL LOOP

  processes sound based acoustic info

  Primary acoustic store: speech perpeption and order in what sounds are presented

  Articulatory process: speech production. Prepares sounds using rehearsal

  Capacity: limited to 2 seconds of what you can say

  Coding: acoustically
• VISUAL SPATIAL SKETCHPAD

  processes visual info

  Visual cache: stores material about color and form

  Inner scribe: handles spatial relationships
• EPISODIC BUFFER

  brings together different types of information from other components. Links to LTM

  Capacity: 4 chunks
• multi store model of memory:

  Environment stimulus ---> SR ----> STM ----> LTM In order for information to go from SR to STM, we must pay attention. Then to move from STM to LTM, it must be rehearsed, otherwise it is lost. To move from LTM to STM, we must retrieve the information
• Working Memory Model:

  A representation of how the short term memory is organised and how it works, proposed by Baddely and Hitch. It suggests STM is an active processor of different types of information using sub units, all connected to the central executive.
• Limitation of the WMMs lack of detail:

  One major issue is that theres not enough detail about how the central executive actually works. If the Central executive controls the whole system there should be more research into its importance. Whilst it is obvious there is an interaction between the components in WMM while performing tasks, it isnt clear how this happens in real life memory. This suggests the central executive component is oversimplified for its advanced systems procedures and therefore the WMM cannot be deemed valid until further evidence is found 
• Strength of the WMMs case study support:

  This model is supported by the case study of KF. This individual suffered a motorcycle accident which damaged his short term memory. His impairment was maily affecting verbal information, and his memory for visual information remained intact. This shows that there are separate stores for visual and verbal information like the WMM displays, supporting this model. However, this can be critiqued as evidence due to it being a case study, there are issues with extrapolating findings from this to the whole population 
• Strength of the WMMS research support:

  Supporting evidence from Baddely and Hitchs lab investigations on dual task performances which demonstrated that we can easily do two different tasks that take up resources in different components such as visual and verbal. They found that when pps were asked to complete a verbal task in the articulatory process and a separate task in the visuo spatial sketchpad, recall wasnt affected. However, when the same pps were asked to complete two simila tasks in the same component, recall on the first task was affected.
• Episodic memory:

  Our ability to recall personal experiences and events(episodes) from our lives.A conscious effort is needed and its time stamped
• Semantic Memory:

  Facts about the world, our knowledge base for everything we know. Less personal and not time stamped, conscious effort must be made
• Procedural memory:

  Actions and skills. Can recall without a conscious effort. Most occur earlier in life through learning important motor skills. Difficult to verbalise
• Research into the types of LTM:

  Tulving was one of the first to realise that the MSMs view of LTM was too simplistic and inflexible.He proposed there were 3 types of LTM stores
• Strength of types of LTMs real world application:

  Real world application: allows psychologists to improve people's lives. Episodic most affected by mild cognitive impairments which highlights the benefit of being able to distinguish.
• Limitation of types of LTM flawed research methods:

  very small samples and case studies, low population validity. Clive wearings case interests many psychologists as it provides useful info to what happens when memory is damaged. However, these ethical case studies are unique to one individual which means findings cannot be generalised to reach conclusions that explain everyone's LTM
• Limitation of types of LTMS unclear explanations:

  the extent to which episodic and semantic are different is uncles. Lots of overlap between the 2 systems as we acquire knowledge based on personal experiences, the semantic memories can originate from episodic. Questions the external validity of the theory
• Strength of types of LTM supporting evidence:

  Clive wearing showed difficulty recalling events after his accident that had happened in the past (episodic memory) but their semantic memories remained intact. Their procedural memories were also intact

  which supports the view that they are different types of LTM as one can be damaged and the other can be intact
• CAPACITY RESEARCH OF LTM:

  The duration is unlimted as shown by Bahrick who found photo recognition of graduating classmates of the 396 participants decreased from 90% to 70% between 15 and 45 years of graduating
• LIMITATION OF RESEARCH INTO CODING OF MEMORY:

  Baddleys study uses artificial stimuli rather than meaningful material. For example the word lists had no meaning to the pps, so Baddelys findings may not tell us much about coding in different kinds of memory tasks, especially in everyday life. When processing more meaningful information, people may use semantic processing even for STM tasks. This suggests the findings have limited application
• STRENGTH OF RESEARCH INTO DURATION OF LTM:

  Bahricks study has high ecological validity due to the researchers investigated meaningful memories (e.g. peoples names and faces). When studies on LTM were conducted with meaningful pictures to be remembered, recall rates were lower. This suggests Bahricks findings reflect a more real estimate of the duration of LTM
• LIMITATION OF RESEARCH INTO DURATION OF STM:

  Peterson and petersons study utuilised artificial stimulus material. This isnt completely irrelivent as we do sometimes try to remember fairly meaningless material such as phone numbers. Even so, recalling consonant syllables doesnt reflect most everyday activities where what we are trying to remember is meaningul, therefore the study lacks ecological validity
• Multi store model of memory:

  Developed by Atkinson and Shiffrin and suggests information flows through 3 seperate stores in a fixed linear order and each store has different roles in the memory process
• STRENGTH OF MSMS CASE STUDY SUPPORT:

  Clinical evidence from case studies such as KF support the model. He suffered brain damage after a motocycle accident; it had no effect on LTM but led to poor performance on many STM tasks, therefore suggesting that they are seperate stores in memory. Cases such as this support Atkinson and Shiffrins model in that they highlight the clear distinction between LTM and STM that each store is seperate
• LIMITATION OF MSMS LACK OF FACE VALIDITY


  It can be argued the model lacks face validity as its clear we dont always need to rehearse information to remember it. There are other things that impact on how information is transferred, for example some things are easier to recall because they are funny or significant. Also, whats significant to one person may not be to another. Therefore, these individual differences in human memory influence how information is transfered to LTM and isnt accounted for by the MSM and theres too much emphasis on rehearsal as the way for memories to be stored in LTM
• LIMITATION OF MSMS SIMPLICITY SUPPORTED BY CASE STUDY:


  It was suggested that LTM can be divided into declaerative memory and procedural memory. For example in the case of Clive wearing, who contracted an infection causing extensive brain damage. He lost his declerative memory ( no memory of wedding) but still has the use of his procedural memory (can still play piano). This is evidence to suggest that the two separate systems of declarative and procedural memory exist in the LTM, therefore undermining the MSM as its far too simplistic.
• STRENGTH OF EWT MISLEADING INFORMATIONS REAL LIFE APPLICATION:


  This research has real life application as it has led to important practical uses for police officers. For example, it highlights the importance of ensuring the police gather information from witnesses immediately after a crime in order to avoid post event discussion distorting eyewitnesses memory. This is a strength as the consequences of inaccurate EWT due to post event discussion can be very seriou therefore the research has important implications for forensic psychology.
• LIMITATION OF EWT MISLEADING INFORMATION METHODOLOGY


  Loftus and Palmers study into leading questions has low ecological validity as pps watched film clips in a laboratory, a very different experience from witnessing a real event (less stressful). What eyewitnesses remember has important consequences in the real world, whereas pps responses don't carry the same importance, therefore pps are less motivated to be accurate.
• STRENGTH OF EWT MISLEADING INFORMATION METHODOLOGY:


  Many studies have been conducted and have regularly found similar results. For example Loftus tended to use a range of controlled experiments illustrating different examples of EWT. Due to the control over extraneous variables in much of Loftus’ research it is easy to replicate. This means researchers using identical procedures should produce similar results, as shown by Loftus’ continuously similar outcomes into how misleading information affects EWT
• EXPLANATIONS FOR FORGETTIN, INTERFERENCE:


  When two lots of information become confuse in memory. One memory blocks another, causing one or both memories to become distorted or forgotten. Forgetting is caused as we  cant access the memory even though they're available.
• 2 TYPES OF INTERENCE AS AN EXPLANATION FOR FORGETTING:

  • Proactive (old interferes with new): old memories affect the recall of new info

  Retroactive (new interferes with old): new memories affect recall of old info