AO3

• Experiments support the proposal that STM and LTM are separate stores

  Glanzer & Cunitz (1966) found a primacy effect and a recency effect when participants recalled words from a list, suggesting STM and LTM are separate, The primacy effect occurs because the first words in the list are rehearsed and transferred to LTM. The recency effect occurs because the last words in the list are still in STM when the words are recalled
• Primacy effect occurs because first words are rehearsed and transferred to LTM


  Recency effect occurs because last words are still in STM when recalled
• Case studies support the proposal that STM and LTM are separate stores

  Milner (1966) studied HM who could not form new long-term memories after hippocampus removal, suggesting LTM is a separate store
• The role of maintenance rehearsal in transferring information from STM to LTM has been criticised
• There is strong evidence that long-term memories can be formed without any rehearsal
• Flashbulb memories


  • Insignificant details surrounding a highly emotional or shocking event (e.g. 9/11) are imprinted directly into LTM without rehearsal
• The MSM cannot explain flashbulb memories, and is therefore weakens as an explanation of how memory works
• The MSM suggests STM is a unitary store


  But case studies show STM has visual and auditory components, supporting the WMM
• Case study of KF

  • KF suffered brain damage and had difficulty with verbal STM but retained visual STM, suggesting STM is not unitary
• Dual task studies


  1. Participants complete a visual tracking task

  2. Participants complete a visual task or verbal task simultaneously
• Participants found the visual task very difficult to complete, but were able to complete the verbal task with ease
• Visual tasks

  Competing for the same limited resources on the VSS
• Visual and verbal tasks

  Occupy separate components of working memory (visual task occupies the VSS, verbal task occupies the PL)
• This supports the WMM's proposal that there are separate stores for visual and auditory processing in STM
• There is evidence from case studies of brain-damaged patients to support the WMM
• Case study

  • Shallice & Warrington (1970) studied the case of KF who suffered brain damage in a motorbike accident
• KF

  • Had difficulty dealing with verbal information in STM
  • Retained a normal ability to process visual information in STM
• KF's PL was damaged


  But his VSS remained intact
• This case supports the WMM's proposal that there are separate stores for visual and auditory processing in STM as it provides evidence that they can be damaged independently of each other
• Dual task studies, such as the one conducted by Baddeley et al. (1975), can be criticised. For example, the tasks artificial and not often encountered in everyday life. This suggests that dual task studies lack ecological validity,
• There are problems with using evidence from case studies of brain-damaged patients. For example, it is difficult to generalise from case studies, as each case has unique characteristics. This weakens the evidence presented by Shallice & Warrington (1970) to support the WMM. 

   
• One weakness is that there is a lack of clarity over the central executive. Cognitive psychologists have suggested that the description of this component is unsatisfactory. It is vague and untestable and may itself be divided into separate sub-components. Baddeley himself recognised this when he said, “The central executive is the most important but the least understood component of working memory”. This suggests that the working memory model hasn’t been fully explained. 
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  There is evidence from brain scan studies to support the suggestion that there are different types of LTM. For example, Tulving asked participants to perform various memory tasks whilst their brains were scanned using a PET scanner. They found that the right prefrontal cortex was involved in recalling episodic memories and the left prefrontal cortex was involved in recalling semantic memories. Separate research has suggested that procedural memories are recalled from the cerebellum. This research suggests that there is a physical reality to the different types of LTM. 
• Case studies of brain-damaged patients

  • Clive Wearing
  • HM
• Episodic memory in Clive Wearing and HM


  • Severely impaired
• Semantic memory in Clive Wearing and HM

  • Relatively unaffected
• Procedural memory in Clive Wearing and HM


  • Unaffected
• Clive Wearing


  • Retained ability to read music and play the piano
• This evidence supports the view that there are different memory stores in LTM as it suggests that one store can be damaged independently of the other stores
• There are problems with using evidence from case studies of brain-damaged patients. For example, it is difficult to generalise from case studies, as each case has unique characteristics. This weakens the cases of Clive Wearing and HM as evidence to support the different types of LTM. 
• Despite different brain areas being involved, the distinction between episodic memory and semantic memory is unclear. They are closely related because semantic memories often originate as episodic memories. This is because new knowledge tends to be learnt from experience. However, over time, there will be a gradual move from episodic to semantic, with the knowledge becoming increasingly divorced from the experience it was learned from. This suggests that episodic memory and semantic memory are not distinct types of LTM.  
• One weakness is that there is evidence that some people are less affected by interference than others
• Example of individual differences in susceptibility to interference

  • Kane & Engle (2000) demonstrated that those with a greater working memory span are less susceptible to proactive interference
• Kane & Engle (2000) study


  1. Gave participants three lists of words to learn

  2. Found that participants with lower working memory spans showed signs of proactive interference when recalling the second and third lists

  3. Participants with higher working memory spans did not show signs of proactive interference
• This suggests that there are individual differences in susceptibility to interference
• Weakness of interference theory

  • Evidence used to support proactive and retroactive interference comes mainly from laboratory experiments
  • Laboratory experiments use artificial stimulus materials such as lists of unrelated words or nonsense syllables
  • These are very different to the types of things individuals try to remember in everyday life
  • Participants may lack motivation to remember information in a laboratory study as there is no consequence for forgetting it
• Research used to support interference theory is low in ecological validity meaning that the findings cannot be generalised to real life settings
• One strength is that there is evidence of interference in real life settings. For example Baddelely & Hitch (1977) asked participants who had played a varying number of rugby union games to remember as many of the teams they had played against as possible. Interference theory was tested by assessing how recall was affected by the number of games played. It was found that forgetting was due more to the number of games played rather than the time passed between games, supporting interference theory.
• One weakness is that it has been suggested that contexts have to be very different before any context-dependent forgetting is seen. Baddeley (1997) suggested that learning material in one room and recalling it in another room would be unlikely to result in much forgetting because these environments are not different enough. This suggests that the findings of Godden & Baddelely (1975) may therefore be explained by the fact that the underwater environment is so different from the environment on land. 
• Godden & Baddeley (1980) experiment


  • Participants learnt a list of words either on land or underwater, then were asked to indicate whether each word from a new list was on the original list, either on land or underwater