Types of long-term memory

• what are the three LTM stores?

  episodic, semantic and procedural memory.
• episodic memories store events (episodes) from our lives.

  this store has been likened to a diary of daily happenings.

  for example, your most recent visit to the dentist.
• episodic memories are complex.

  they are time-stamped- you remember when they happened.

  they involve several elements- people, places, objects, and behaviours are woven into one memory.

  you have to make a conscious effort to recall them.
• semantic memory stores our knowledge of the world.

  this is like a combination of an encyclopedia and a dictionary.

  for example, it includes knowledge of such things as applying to university, the taste of an orange, and the meaning of words.
• semantic memories are not time-stamped.

  for example, you do not usually remember when you first learned about psychology.

  semantic knowledge is less personal and more about the knowledge that we all share.
• procedural memory stores memories for actions and skills.

  these are memories of how we do things.

  for example, driving a car or playing table tennis.
• recall of procedural memories occurs without awareness or effort.

  these are the sorts of skills we might even find quite hard to explain to someone else because we recall these memories without conscious awareness.

  for example, explaining how to ride a bicycle or trying to tell someone how you change gear when driving because you do it without having to recall how to do so.
• strength of episodic memory: supported by case study evidence

  clinical studies of amnesia (HM and Clive wearing) showed both had difficulty recalling events that had happened to them in their pasts. but their semantic memories were relatively unaffected (e.g. HM did not recall stroking a dog half an hour earlier, but he did not need the concept of 'dog' explained to him). this supports the view that there are different memory stores in LTM because one store can be damaged but the others left unaffected.
• strength of types of LTM: identifying different LTM stores has real-life application

  psychologists can target certain kinds of memory in order to improve people's lives. belleville et al. found that episodic memories can be improved in old people with mild cognitive impairments. training led to improvements (compared to control group). this highlights the benefit of distinguishing between different types of LTM- it allows specific treatments to be developed.
• limitation of types of LTM: problems with clinical evidence

  evidence is often based on clinical cases (e.g. HM and Clive wearing) about what happens when memory is damaged. there is a serious lack of control of different variables in these studies (e.g. cannot control the precise location of the brain damage or personality variables). so it is difficult to generalise from these case studies to determine the exact nature of LTM.
• strength: support from brain scan studies

  tulving et al. had participants perform various memory tasks while their brains were scanned with a PET scanner. episodic and semantic memories were in the prefrontal cortex; semantic in the left side and episodic in right prefrontal cortex. this shows a physical reality in the brain to the different types of LTM, confirmed in many research studies, supporting its validity