3. Types of LTM

• Who proposed the idea of types of LTM?

  • Tulving - cognitive psychologist
  • MSM view of LTM was too simplistic
  • Three memory stores containing different types of memory
• Episodic memory

  • Refers to our ability to recall events from our lives eg. a recent visit to a dentist
  • Complex, explicit and declarative memories
  • Time stamped and store info about how events relate to each other in time
  • All elements such as people, objects and behaviours are interwoven to produce a single memory
  • Make a concious effort to recall them
• Semantic memory

  • Shared knowledge of the world and is likened to an encylopedia and dictionary
  • Explicit and declarative memories
  • Memories are not time stamped and we don't remember when we first heard them
  • Less personal and more about facts we all share
  • Constantly being added to
  • Less vulnerable to distortion and forgetting than episodic
• Procedural memory

  • Our memory for actions or skills eg. driving a car
  • Implicit and non-declarative memories
  • Recall without conscious efforts - automatic through practice
  • Skills we find hard to explain to others
• Strength - evidence from famous case studies

  • HM and Clive Wearing - episodic memory in both men was severely impaired due to brain damage but their semantic memories were relatively unaffected as they still understood the meaning of words
  • HM could not recall stroking a dog earlier in the day but did not need to have the concept of 'dog' explained to him
  • Procedural memories also still intact
  • Clive Wearing (professional musician) still knew how to read music and play the piano
  • This evidence supports Tulving's theory
• Counterpoint - case studies

  • Clinical studies are not always perfect as they lack control of variables
  • Brain injuries are usually unexpected and the researcher has no way of controlling what happened to the pps before and after the injury as well as having no knowledge of the individuals memory before the damage
  • Difficult to judge exactly how much worse it is afterwards
  • Lack of control limits how much clinical studies can tell us about types of LTM
• Strength - allows psychologists to help people with memory problems

  • As people age they experience memory loss but research shows this seems to be specific to episodic memory - harder to recall personal events that occurred recently
  • Sylvie Belleville devised an intervention to improve episodic memories in older people. The trained pps performed better on a test of episodic memory after training than a control group
  • Enables treatments to be developed
• Limitation - conflicting research findings linking types of LTM to areas of the brain

  • Buckner and Petersen reviewed evidence regarding the location of semantic and episodic memory
  • Concluded semantic memory is located in the left side of the prefrontal cortex and episodic memory on the right
  • However other research links the left prefrontal cortex with episodic retrieval (Tulving)
  • Challenges neurophysiological evidence to support types of memory as there is poor agreement on location