types of long-term memory

Question 1

who proposed the different types of LTM and why?

Answer 1

• endel tulving (1985)
• he realised that the MSM’s view of LTM was too simplistic and inflexible
• he proposed that there are 3 LTM stores containing different types of information

Question 2

what are the 3 types of LTM stores?

Answer 2

• episodic memory
• semantic memory
• procedural memory

Question 3

describe the 2 ways in which long-term memories can be categorised

Answer 3

• explicit (declarative) or implicit (non-declarative)
• explicit memories include knowledge for events and facts (knowing that)
• implicit memories are skilled behaviours (knowing how) which are largely unconscious

Question 4

what does episodic memory refer to?

Answer 4

• how ability to recall events (episodes) from our lives
• eg. your most recent visit to the dentist

Question 5

in what 3 ways are episodic memories complex?

Answer 5

1. they are time-stamped: you remember when they happen as well as what happened. they also store information about how events relate to each other in time
2. your memory of a single episode will include several elements eg. people and places, objects and behaviours. all of these memories are interwoven to produce a simple memory
3. you have to make a conscious effort to recall episodic memories. you do this quickly but are still aware that you are searching for your memory

Question 6

what does the semantic memory contain?

Answer 6

• our shared knowledge of the world
• eg. how to apply to university, the meaning of words
• it also contains your knowledge of many concepts such as ‘animals’ or ‘love’
• contains an immense collection of material which is constantly being added to

Question 7

how are semantic memories different from episodic ones?

Answer 7

• not time-stamped
• less personal, more about the facts we all share
• less vulnerable to distortion and forgetting

Question 8

what is procedural memory?

Answer 8

• memory for actions or skills
• we can recall these memories without conscious awareness or much effort
• these skills may be difficult to explain to someone else
• eg. driving a car

Question 9

evaluation: clinical evidence from famous case studies of HM and clive wearing

Answer 9

• episodic memory in both men was severely impaired to brain damage caused by an operation (HM) and an infection (clive wearing)
• however, their semantic memories were relatively unaffected
• eg. HM could not recall stroking a dog half an hour earlier but did not need to have the concept of ‘dog’ explained to him
• procedural memories were also intact eg. both still knew how to walk and speak
• clive wearing (a professional musician) knew how to read music, sing and play the piano but cannot remember the names of his children
• this supports the idea that one store can be damaged but others unaffected

Question 10

evaluation: clinical studies are not perfect

Answer 10

• variables are not controlled
• brain injuries experienced by participants are usually unexpected
• the researcher had no way of controlling what happened to the participant before or during the injury
• the researcher has no knowledge of the individual’s memory before the damage
• without this, it is difficult to judge exactly how much worse it is afterwards
• this limits what clinical studies can tell us about different types of LTM

Question 11

evaluation: conflicting research findings linking types of LTM to areas of the brain

Answer 11

• buckner and petersen (1996) reviewed evidence regarding the location of the semantic and episodic memories
• they concluded that 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 encoding of episodic memories and the right prefrontal cortex with episodic retrieval (tulving et al. 1994)
• this challenges any neurophysiological evidence to support types of memory as there is poor agreement on where each types might be located
• this limits the extent to which conclusions can be drawn regarding the neurostructural nature of the LTM and any treatments based on these assumptions

Question 12

evaluation: real-world application

Answer 12

• allows psychologists to help other people with memory problems
• eg. as people age, they experience memory loss
• research has shown that this seems to be specific to episodic memory ie. it becomes harder to recall memories of personal events / experiences that occurred relatively recently but past episodic memories remain intact
• belleville et al. (2006) devised an intervention to improve episodic memories in older people
• the trained participants performed better on a test of episodic memory after training than a control group
• this shows that distinguishing between types of LTM enables specific treatments to be developed

Question 13

evaluation: ambiguity between different stores

Answer 13

• tulving (2002) said that episodic memory is a ‘specialised subcategory’ of semantic memory, so they are essentially the same store
• his research shows that some people with amnesia have a functioning semantic memory alongside a damaged episodic memory
• he also concluded that it is not possible to have a functioning episodic memory with a damaged semantic memory
• however, hodges and patterson (2007) found that some people with alzheimer’s disease could form new episodic memories but not semantic memories