Types of long term memory

• Tulving (1985)


  One of the first cognitive psychologists to realise that the multi-store model's view of the LTM was too simplistic and inflexible
• LTM stores proposed by Tulving


  • Episodic memory
  • Semantic memory
  • Procedural memory
• Episodic memory


  • Refers to our ability to recall events (or episodes) from our lives
  • They are time-stamped
  • Memory of a single episode will include several elements e.g. people, places, objects and behaviours all interwoven into a single memory
  • They are recalled using conscious effort and can be expressed with words
• Semantic memory


  • Refers to memories that relate to knowledge of the world
  • Semantic knowledge less personal and more about facts we all share
  • Require conscious effort to recall and can be expressed in words
• Procedural memory


  • Refers to our memory for actions, skills i.e. how we do things
  • We can recall these memories without conscious awareness or a great deal of effort
• Case studies of HM and Clive Wearing


  • Episodic memory was impaired due to amnesia
  • Semantic memory was intact
  • Procedural memory was intact
• Neuroimaging evidence


  Physically proves there are different types of LTM
• Tulving et al.'s (1994) experiment


  1. Participants performed various memory tasks whilst their brains were scanned using a PET scanner

  2. Episodic memories were recalled from the right PFC

  3. Semantic memories were recalled from the left PFC
• Practical application


  Differentiating between different types of LTM may lead to improved, increasingly targeted treatments for mild cognitive impairments
• limitation


  There is a lack of generalisability to the general public and reduced validity. Psychologists can learn a lot from case studies of people with brain injuries such as HM and Clive Wearing. However, case studies tend to have poor control over variables. They also tend to be done on small samples (sometimes even a sample of one!) and look at very novel and unique cases.
•  Cohen and Squire drew a distinction between declarative and nondeclarative memories.

  Declarative memories must be recalled consciously (i.e. episodic and semantic)

  Nondeclarative memories may be recalled unconsciously (i.e. procedural)