Types of LTM

• LTM


  The permanent memory store.

  Coding is mainly semantic

  Capacity is unlimited

  Duration is up to a lifetime
• Tulving (1985)


  Tulving criticised Atkinson and Schiffrin's (1965) MSM of memory because he believed it oversimplified the LTM and STM stores.

  
  

  Tulving proposed that there were 3 separate stores for LTM

  - Procedural

  - Semantic

  - Episodic
• declarative knowledge vs non-declarative knowledge


  All long-term memories are categorised as either explicit (declarative) or implicit (non-declarative).

  
  

  Implicit (non-declarative) knowledge involves 'knowing how' to do things - these are skilled behaviours, which are largely unconscious.

  
  

  Explicit (declarative) knowledge involves 'knowing that' - involves some degree of conscious effort. Information is consciously brought to mind and 'declared'.
• Evidence for the distinction between declarative and procedural memory:

  Research on patients with amnesia. Following the onset of amnesia, typically, patients have difficultly retaining episodic and semantic information (ability to retain declarative information is impaired).

  
  

  Their memory for events and knowledge acquired before the onset tends to stay intact, but they can't store new episodic or semantic memories.

  
  

  However, their procedural memory appears largely unaffected, being able to recall skills they've already learned, and acquire new ones.
• Procedural Memory


  A part of the implicit LTM knowing how to ride a bike and swim - "knowing how" to do things.

  
  

  Through repetition and practice, they become automatic, doesn't involve conscious thought. This means that the skill can be performed with little awareness of the steps needed to carry it out - non-declarative.

  
  

  These memories are implicit - involve motor skills and behavioural habits.

  
  

  It's important that these become like second nature to us so that we can focus our direct attention onto other everyday tasks we perform at the same time.

  
  

  Procedural memories are associated with the cerebellum and motor cortex.
• Semantic Memory


  A type of explicit memory.

  
  

  Included memory for general knowledge, facts, concepts and meaning about the world around us.

  
  

  These memories need to be recalled deliberately, involves conscious thought, and is declarative.

  
  

  Generally, semantic memories often start as episodic memory as we learn from experience but gradually lose their association with a specific event and transition into semantic memories.

  
  

  They aren't time stamped, nor do they remain closely associated with a particular event (episode).

  
  

  The strength of semantic memories is determined by the strength of emotions experienced when the memory is coded.

  
  

  Semantic memories are generally stronger in comparison to episodic, and are associated with the temporal lobe.
• Episodic Memory


  A type of explicit memory.

  
  

  Memory for past personal experiences - of an event or group of events forming a large sequence.

  eg: going to university, a birthday party.

  
  

  This type of LTM is concerned with personal experience and have 3 elements:

  - specific details of the event

  - the context

  - the emotion

  
  

  Contains memories of when the event occurred as well as the people, behaviours, objects and places involved.

  
  

  The strength of episodic memories is determined by the strength of the emotions experienced when the memory is coded.

  
  

  Conscious effort is required to retrieve episodic memories.

  
  

  Episodic memories are associated with the hippocampus and temporal lobe.
• Amnesia


  A partial or complete loss of memory due to loss of consciousness, brain damage, or some psychological cause
• Case Study - Clive Wearing

  Suffers from a severe form of amnesia (retrograde and anterograde) due to an aggressive viral infection which caused damage to his hippocampus and associated areas

  Gives us insight into how memory is distributed in the brain and not localized to the hippocampus

  
  

  Before the infection, Clive was a world class piano player and can still play incredibly well - suggests that the areas of the brain related to procedural memory is intact

  
  

  He can also remember his children from a previous marriage, however he is unable to remember their names

  He remembers his second wife Deborah and greets her joyously every time they meet, believing each time that he hasn't seen her in years

  
  

  Suffered damage to his episodic and semantic memory, but has retained his procedural memory (and some aspects of his semantic memory)
• Clive Wearing - support

  This evidence supports Tulving's view that there are different memory stores in LTM - one store can be damaged but other stores are unaffected
• Anterograde Amnesia


  An inability to form and store new memories.
• Retrograde Amnesia


  An inability to retrieve information from one's past.
• Limitation of using clinical cases of brain damage to study memory

  Idiographic, rare

  Lower population validity, findings are specific and can't be easily applied to the whole population

  
  

  Also, there is a lack of control over variables

  The researcher had no way of controlling what happened to the participant before or during the injury

  Limited knowledge of the individual's memory before the damage

  This limits what clinical studies can tell us about different types of LTM
• A03 - real world application (P)


  Another strength is that understanding types of LTM allows psychologists to help people with memory problems
• A03 - real world application (E)

  For example, as people age, they experience memory loss.

  
  

  But, research has shown this seems to be specific to episodic memory - it becomes harder to recall memories of personal experiences that occured relatively recently, but past episodic memories remain intact
• A03 - real world application (E)

  Belleville (2006) compared the performance of older people suffering with a mild cognitive impairment who received memory training with that of a control group who did not.

  
  

  If was found that pp's in the experimental group performed better on a test of episodic memory.
• A03 - real world application (L)


  This shows that distinguishing between types of LTM enables specific treatments to be developed.
• A03 - nomothetic/idiographic (P)


  The study of LTM adopts both a nomothetic and an idiographic approach.
• A03 - nomothetic/idiographic (E)

  Nomothetic as it attempts to generate universal laws of cognitive processes including our different types of LTM.

  
  

  But it also uses case studies such as the case of Patient HM and Clive Wearing - idiographic.
• A03 - scientific principles

  The scientific principles are adopted to a large extent, with the investigation of different types of long-term memories when conducted in a laboratory, but case studies often lack control due to their nature.