Memory

• Multi-store Model AO1:

  • Developed by Atkinson and Shiffrin to show how info flows from one storage system to another in a linear way
  • Made of three permanent unitary stores
  • Info enters the senses via the Sensory Register where it is coded in its original form
  • When attention is paid to it it enters the STM
  • Maintenance rehearsal in the form of acoustic repetition holds information in STM and moves it to LTM, any new information or distractions preventing rehearsal in the STM will push the information out and it will be lost.
• a = Sensory Register

  b = attention

  c = maintainence rehearsal

  d = Short-Term Memory

  e = rehearsal

  f = Long-Term Memory

  
• MSM AO1:

  Sensory register:

  • capacity = all sensory experience
  • duration = 0.5 seconds
  • coding = original form

  STM:

  • capacity = 7 +/- 2 items
  • duration = 0-18 seconds
  • coding = acoustic

  LTM:

  • capacity = unlimited
  • duration = lifetime
  • coding = semantic
• Sensory Register AO3:

  • Sperling had participants look at a grid of letters for < 1 second and were asked to recall them. They could remember only 4/5. Then they had to recall single rows of letters when different tones were heard. High tone for top row, medium for middle and low for the bottom. On average 3 items were recalled. This shows that all the letters entered awareness, but only those attended to could be recalled. Research supports the idea that the SR has a large capacity but a very short duration.
  • Evaluation: high internal validity, low ecological
• STM Capacity AO3:

  • Jacobs did a lab-based digit span test. 443 female students had to repeat back a string of numbers/letters in the same order; this increased in length until they no longer could. On average they could recall 7 letters and 9 numbers (so capacity = 7+/- 2) It has also been found that chunking can increase capacity
  • Evaluation: High internal validity, low ecological. Findings have been repeated and found to be reliable.
• STM Duration AO3:

  • Peterson and Peterson had 24 students briefly look at nonsense trigrams then count backwards in threes. The counting prevented rehearsal so that only STM was being tested. They were asked to recall the trigrams; with each trial increasing by 3 seconds. Most people remembered 80% after 3 seconds, but less than 10% after 18 seconds.
  • Limited population sample means it is unrepresentative
• STM Coding AO3:

  • Baddeley lab experiment with 75 participants in 4 groups. They were given a list of 5 words and asked to recall them in order. Participants who were given acoustically similar words performed worst, average 55%. This suggests STM is coded acoustically.
  • Lab environment means high internal validity, but artificial and meaningless task means low ecological.
• (V)LTM capacity AO3:

  • Linton kept a daily diary, with one word representing each day. After 7 years she recalled 11000 events with 70% accuracy when given the cue. This supports the huge capacity of the LTM.
  • Case study so low population validity.
• (V)LTM Duration AO3:

  • Bahrick et al used high-school yearbooks to test LTM for names and faces, using 400 participants aged 17 - 74. Participants were given a free–recall test where they were asked to name all the people in their year. For participants who had left school ~50 years before the experiment, recall stood at 70-80%. Considering the duration as well as the fact that the latter group were on average much older, this is a small difference and shows the potentially life time duration of LTM.
  • Real life stimulus material so high ecological validity
• LTM Coding AO3:

  • Baddeley put 75 participants into 4 groups. Each heard a different list of 5 words. 20 mins after they were asked to recall them in the correct order (repeated x4). Participants given semantically similar words performed worst -> it seems there is semantic confusion in LTM, suggesting LTM is encoded on a semantic basis.
  • Lab setting ensured control and standardisation, good internal validity as extraneous variables like noise have been controlled for, the findings don’t apply in real life so it is not a valid test of everyday memory and the results lack ecological validity.
• Processes involves in MSM:

  • If attention is focused on sensory memory, it is transferred to STM. Anything else is ignored and lost to save space and prepare for more new information.
  • Information is maintained in STM through maintenance rehearsal, which takes the form of acoustic repetition. If information is not rehearsed it will decay as the duration is thought to be around 18 seconds. Adding meaning, known as elaborative rehearsal, leads to transfer from STM to LTM. The idea is that the more something is rehearsed the better it will be remembered.
• Rehearsal AO3:

  • Murdock gave participants a list of 20 words and asked to immediately recall them; they tended to remember the first and last words and are more likely to forget those in the middle of the list. This is called the serial position effect.
  • This supports separate LTM and STM stores because they observed this primacy-recency effect. Words early on in the list were put into LTM because the person has time to rehearse the word, and words from the end went into STM.
  • Considered a too simple explanation. The model ignores factors such as motivation, strategy and significance.
• Multi-store model AO3:

  • Case study - Clive Wearing has amnesia because a virus damaged areas in his brain associated with memory, i.e. the hippocampus which transfers STM to LTM. E.g. he will forget a question he has been asked or a person he has just seen as little as 7-30 seconds later. This supports the MSM as it show that STM and LTM are separate stores. However Clive has lost his LTMfor events but his LTM for how to do things such as play the piano remains unaffected. This criticises the MSM as it suggests there is not just one type of LTM but several.
  • Capacity research Jacobs and Linton
• Multi-store model more AO3:

  • STM coded acoustically and LTM semantically Baddeley research
  • The MSM claims rehearsal is required to make LTMs, however this is not the case as the type and meaningfulness of information is also important. Instead the idea of ‘deep processing’ has been proposed as the way in which LTM is formed. This idea states that originally well learning information with more meaning will be more likely to become lasting LTM. This criticises rehearsal as being too simple.
  • Comparison with WMM which is more complex with different types of information but only includes STM.
• Working Memory Model general AO1:

  • Proposed by Baddeley and Hitch who viewed the STM as an active store based on processes that holds several pieces of information while they are being worked on with four separate components.
  • A key assumption of the model is that we can do two tasks together if they use different slave systems but not if they use the same system as this overloads it and is too difficult.
• WMM diagram:

  1 = Phonological Loop

  2 = Central Executive

  3 = Episodic Buffer

  4 = Visuospatial Sketchpad

  
• Central Executive AO1:

  • This is the command centre for working memory (the manager) and is used with problem solving tasks and decision making.
  • It has limited capacity and duration as it is not a store but more of an attention mechanism. It can process/code any type of incoming information. Its function is to delegate tasks accordingly to the relevant slave system and focus our attention, attaining a balance between tasks when attention needs to be divided e.g. talking whilst driving.
• Central Executive AO3:

  • Bunge et al used brain scans to see which parts of the brain were most active when participants were completing two tasks (reading a sentence and recalling the final word in a sentence). Participants either did this simultaneously, or one after the other. They found that the same brain areas were active in both the dual and single task conditions, but there was significantly more activation in the dual task indicating increased attentional demands shown by brain activity. This highlights the important role of the central executive that involves directing attention.
• Phonological Loop AO1:

  • (‘slave’ system) Temporary store with short duration and limited capacity. Codes spoken and written material, (when you read written info you speak aloud the words in your mind and thus convert it to auditory info). Primarily an acoustic store so confusions can occur with similar-sounding words. Baddeley further subdivided this into the 'phonological store' which holds auditory memory traces for a few seconds before they decay and the 'articulatory process' which allows words/sound that are heard or seen to be stored through rehearsal by silently repeating them.
• Phonological Loop AO3:

  • Baddeley did research into ‘the word length effect’; lists of short words are remembered better than longer words. Short words can be silently articulated faster than longer words and therefore more of them can be articulated in the time (approx 2 secs) before the trace decays. If the participants in a study are then asked to say something aloud at the same time as they are rehearsing material, then memory for the rehearsed material is impaired. This provides evidence for the existence of an articulatory rehearsal process with a duration of 2 seconds.
• Visuo-spatial Sketchpad AO1:

  • (slave system) Handles non-phonological information. Temporary store for visual and spatial items and the relationships between them; essentially, a store for what items are and where they are located. Codes information in the form of its visual features e.g. size & shape. Information is rehearsed and encoded through the use of ‘mental pictures’. Within the VSS is the inner scribe that deals with spatial and movement information such as planning out routes and the visual cache, which is a limited capacity store for visual info about form and colour.
• Visuo-spatial Sketchpad AO3:

  • Gathercole & Baddeley found p’s had more difficulty doing two visual tasks compared to doing one visual and one auditory task. They asked one group to follow a moving point of light and at the same time describing the angles of a letter ‘F’. They asked a second group to follow the light and at the same time perform a verbal task. The second group had less difficulty. This study supports the existence of separate stores for different types of info and the concept that they can work independently.
• Episodic Buffer AO1:

  • (slave system) added in 2000 to explain how information from different subsystems in different formats could be combined, and how it was capable of communicating with long-term memory.
  • It is claimed to be a store of limited capacity capable of holding any kind of information. It is a ‘buffer’ as it has a limited capacity temporary store that forms an interface or link between a range of systems all having different memory codes. It is ‘episodic’ as it is capable of holding episodes; integrated chunks of information that then became accessible to working memory.
• Episodic Buffer AO3:

  • Chunking - Initially proposed by Miller and assumes that STM memory is capable of holding only a limited number of chunks, regardless of the size of each chunk. Baddeley showed the power of chunking by performing a simple lab experiment asking people to immediately recall wither unrelated words or words chunked together in a short meaningful sentence. Participants recalled around 7 sentence words and only around 5 unrelated words.
• Working Memory Model AO3:

  • Central executive - there is little evidence for how it works/what it does. It's hard to measure as it doesn't work on a specific type of info. Bunge et al research supports the role of the central executive in directing attention but it lacks ecological validity.
  • Comparison to MSM - the WMM is a much more complex account of STM than the MSM which claims it's just one unitary store. The evidence supports the WMM’s more complex ideas about different types of STM. However the WMM is an incomplete model of memory as it does not theorise about the workings of LTM.
• Working Memory Model more AO3:

  • Application - Researchers generally agree that STM is made up of a number of components. This means the WMM has real life applications as it makes sense of a range of real tasks: e.g. reading (PL); problem solving (CE). Understanding the components of this memory system and their interaction might allow us to improve our WM. It has been suggested that some cognitive disorders like ADHD, are due to deficits in WM and could be improved by using WM training programmes, e.g. teaching people to break down tasks into component parts to ease demands on the CE.
• Types of LTM AO1 - procedural:

  • memories of motor skills, actions, muscle memories, e.g. riding a bike
  • They are thought to be located in the basal Ganglia and cerebellum
  • They are unavailable for conscious inspection and non-declarative as they do not enter conscious awareness
  • They are more resistant to forgetting/amnesia
  • We usually do not recall when we learned them
• Types of LTM AO1 - episodic:

  • memories of life events, e.g. our family holiday (ex must be personalised
  • They are thought to be located in the hippocampus
  • They are declarative as they enter conscious awareness
  • Common to lose as a result of forgetting/amnesia
  • Stored with reference to time/place
• Types of LTM AO1 - semantic:

  • knowledge/fact based, e.g. remembering the capital of France
  • They are thought to be stored in the hippocampus
  • They are declarative as they enter conscious awareness
  • Common to lose as a result of forgetting
  • We may not recall when they were learned/encoded
• Types of LTM AO3:

  • Case study to support - HM had hippocampus removed to control his severe seizures. After this he could no longer make episodic memories. However Milner discovered his procedural LTM still worked as he improved at drawing a star in a mirror despite not remembering doing it.
  • Methodology - evidence based on unique individual with a serious case meaning results are not representative or generalisable. Also lacks internal validity due to participant variables, e.g. HM had a poor education due to seizures which could account for memory issues.
• Types of LTM more AO3:

  • Clive Wearing case study - had amnesia due to a herpes attacking his brain and damaging his hippocampus. He lost his long term episodic memory but retained his procedural memory for things like playing the piano.
  • Neuroimaging - Tulving et al got participants to perform memory tasks while their brains were PET scanned. They found that the left prefrontal cortex was involved in recalling semantic memories and the right prefrontal cortex was involved in recalling recalling episodic memories. Adds scientific credibility to the unreliable case studies.
• Explanations for forgetting AO1 - interference:

  • Explains forgetting as two lots of information becoming confused.
  • Proactive is where old learning affects recall of new information, e.g. not remembering your new girlfriend's name as you keep thinking of the old girlfriend's name.
  • Retroactive is where new learning affects recall of/overwrites old information e.g. learning a new postcode and forgetting your old one.
  • Interference is more likely to occur when the two pieces of information are similar.
  • The impact of passage of time is the cause forgetting.
• Explanations of forgetting AO3 - interference:

  • Lab - McGeoch and McDonald gave participants a list of words that they memorised. They were given a second list - for one group the words were different (100% recall of first list after) but for the other they had similar meanings (12%). Supports that interference more likely when info is similar.
  • Field - Baddeley and Hitch tested rugby players’ memory of players they had played against. Those who had played in fewer games recalled proportionately more names than those who had played in more. Attributed to interference due to more info.
• Explanations of forgetting AO1 - retrieval failure:

  • Tulving proposed the concept of ‘cues’ - signposts to memories that make recall possible. If these are missing info will be forgotten. So forgetting is a problem with accessibility and not availability.
  • Good ‘face validity’, e.g. ‘tip of the tongue phenomenon’. If one aspect of the target word is remembered then we will be able to access the whole memory.
  • Argues that info in LTM is only accessible if the right cues are present. So info that has been well learnt is less likely to be forgotten as we have made many connections to it.
• Explanations of forgetting AO1 - retrieval failure:

  • Necessity of cues during encoding and recall is known as the encoding specificity principle. Tulving found that the closer the cue to the target word the better our recall. This is how mnemonics and memory tricks often work.
  • Organisation cues: based on categories which help to group items in memory.
  • Context cues: based on external environment
  • State cues: based on emotional or physical state
• Explanations of forgetting AO3 - retrieval failure:

  • Tulving and Pearlstone - participants had to recall 48 words belongingto 1/12 categories. Each word was preceded by its category. If the cue was then present at recall then recall was 60%. If not then it fell to 40%. Practical applications are be limited as we cannot always categorise real life info.
  • Godden and Baddeley - tested context cues by having divers learn and recall info in/out of the water. Results showed that words learnt and recalled in different contexts were more likely to be forgotten. Very unrealistic circumstances.
• Factors affecting the accuracy of EWT AO1 - misleading information:

  • Memories are reconstructed over time using schemas so EWT can be unreliable as they are biased by schemas active at time of recall.
  • Leading questions influence a participant's answer. Words can activate schema e.g. 'what did the man steal?' even if you didn't know their gender.
  • Post-event discussion occurs with other witnesses/interviewers and can contaminate a memory. They may combine misinformation or reach a consensus view to conform. This can lead to false convictions as EWTs are used as primary evidence in court.
• Factors affecting the accuracy of EWT AO1 - anxiety:

  • Researchers have looked at the relationship between anxiety and recall accuracy as most crimes involves some level of anxiety.
  • Some suggest anxiety diverts attention froom important features of a crime whereas others suggest it improves focus
  • The Yerkes Dodson inverted U hypothesis suggests that improved accuracy during recall is associated with moderate levels of arousal - if it is too high or low then accuracy decreases.
• Factors affecting the accuracy of EWT AO3 - misleading information:

  • Loftus and Palmer leading questions- asked American students to estimate the speed of a car crashing in a film but changed the verb. 'smashed' gave the highest estimate of 41 mph and 'contacted' the lowest at 31 mph.
  • Gabbert et al post event discussion - had 60 students and 60 adults watch a video of a girl stealing and put them into pairs to discuss. In each pair, only one had watched a perspective that actually showed her stealing. In a questionnare, 71% recalled info they had not seen and 60% said she was guilty.
• Factors affecting the accuracy of EWT AO3 - anxiety:

  • Johnson & Scott - Condition 1: Ps heard a discussion taking place in the lab about equipment failure and a man emerged holding a pen with grease on his hands. Condition 2: Ps heard a hostile exchange and breaking glass. A man emerged holding a knife covered in blood. When asked to identify the man from photos, ps in condition 1 were 49% accurate, compared with 33% in condition 2. ‘Weapon focus effect’ means that ps have good recall of the central detail of the crime like the weapon, but poor memory for the peripheral details.