Memory - PAPER 1 Flashcards
LTM vs STM
LTM:
- duration - up to a lifetime
- capacity - unlimited
- coding - semantic
STM:
- duration - 18/30 seconds
- capacity - 5/9 bits of info
- coding - acoustic
Baddeley (1966) study (coding of STM and LTM)
- gave participants 4 lists of words, acoustically similar/ unsimilar and semantically similar/unsimilar, words being presented one at a time
- repeated measures design
- participants were asked to recall the order of the words immediately after and after 20 mins
FINDINGS: - acoustic confusion - difficulty remembering acoustically similar works when participants were asked to recall immediately
- semantic confusion - when asked to recall after 20 mins.
SO: - STM prefers to code acoustically and LTM prefers to code semantically
EVALUATIOM
- conclusions have stood the test of time
- led to the creation of the multi-store model (important step in our understanding of memory system)
- BUT artificial stimuli: word lists had no personal meaning, so lack of ecological validity. people may use semantic coding for STM.
Josepf jacobs (1887) study on capacity of STM
- used a digit span test to assess the capacity of STM.
- he found that the average amount of letters remembered was 7.3 and numbers remembered was 9.3
EVALUATION:
- findings have been confirmed by newer studies
- BUT: lack of ecological validity because numbers and letters have no personal meaning
George miller (1956) study on STM capacity
- found that people could absorb 7 (plus or minus 2) new pieces of information in STM at a time.
- founded chunking (grouping letters or digits into chunks, making them easier to remember)
EVALUATION:
- may have overestimated STM capacity
- Other psychologists reviewed other research and found the capacity may only be 4 (plus or minus 2) chunks
- some psychologists found 4 chunks is the limit for STM with visual info.
Peterson and Peterson (1959) study on duration of STM
- participants given a nonsense trigram to remember, together with a 3 digit number.
- participants had to recall the trigram after a retention interval of 3, 6, 9, 12, 15 or 18 seconds.
- during the retention interval, participants had to count backwards from their 3 digit number, to ensure they weren’t recalling the trigram
- recall got worse as the delay grew longer and it was found that the duration of STM is 18-30 seconds
EVALUATION
- artificial stimuli, although, not completely irrelevant as we do sometimes have to recall meaningless info (phone numbers, postcodes etc.)
- recalling trigrams doesn’t reflect most everyday memory activities where what we are trying to remember is meaningful
Bahrick et al (1975) (study for how long LTM lasts)
- used 392 17-74 year olds
1) photo recognition task:
- participants supplied with old yearbook photos and asked to pick out who they had gone to school with.
- 90% accuracy if graduated within 15 years.
- 70% accuracy if graduated within 48 years
2) Free recall task:
- participants not supplied with old yearbook photos - just asked to recall who they had gone to school with
- 60% accuracy if graduated within 15 years
- 30% accuracy if graduated within 48 years
SO: LTM can potentially last a lifetime
EVALUATION
- high external validity as researchers investigated meaningful memories
- when other research has been done with meaningless pictures, recall rates were lower.
diagram of multi-store model of memory
sensory memory/ register properties
- coding - modality specific
- duration - less than half a second
- capacity - very high (e.g many cells in retina of eye, all storing data)
what is the iconic sensory register store
visual images kept for a short period
what is the echoic sensory register store
auditory senses kept for a short period
George Soerling (1960) - study for duration of iconic sensory register
George sperling (1960):
- participants asked to recall a whole grid recalled worse than participants asked to recall just part of a grid
- proves the rapid decay of the iconic memory store
Murdock (1962) - study for evidence of the multi-store model
Murdock (1962)
- participants learnt lists of words one at a time for 2 seconds per word, and then recalled the words in any order
- words at end of list were recalled better (recency effect) and words at the beginning of the list (primary effect), but words in the middle not at all
- evidence for STM and LTM: last words in STM and first few words in LTM because rehearsal took place
study for evidence of the distinction between LTM and STM
Shallice and Warrington (1977):
- Patient had been in a motorcycle crash where he had sustained brain damage
- his LTM was unaffected but he was only able to recall the last bit of info he had heard in his STM
- had a normal visual STM capacity, but an abnormally low verbal STM capacity
Endel Tulving (1985) - study for the 3 LTM stores
- one of the first cognitive psychologists to realist the multi-store models view of LTM was too simplistic and inflexible.
- he proposed there were 3 LTM stores (episodic, semantic and procedural)
- research into LTM has been conducted on individual patients, so might not be good for generalising.
episodic memory
- linked to personal experiences
- time stamped
- has context and emotions linked to it
- explicit - conscious effort is needed to recall them
semantic memory
- shared knowledge of the world
- e.g capital of France is Paris
- this information can be generalised
- explicit - conscious effort needed to remember
procedural memory
- skill based
- automatic after practice/repetition
- implicit - less conscious effort needed to remember
- allow us to multitask
working memory model diagram
what is the central executive
- attentional process that monitors incoming data
- decides how to process incoming information
- very limited processing capacity (similar to sensory register)
- supported by LTM, otherwise nothing would be understood
what is the phonological loop
- processes auditory information and preserves the order in which the information arrives.
- has two sub-divisions:
1) the phonological store - stores the words you hear
2) the articulatory process - allows for maintenance rehearsal (i.e repeating words you hear in a loop in order to keep them in the working memory). the capacity of this loop is said to be 2 seconds of what you can say.
what is the visuo-spacial sketchpad
- stores visual and/or spacial info when required.
- capacity of 3-4 objects
- made up of two components:
1) the visual cache - stores visual data
2) the inner scribe- records the arrangement of objects in the visual field
what is the episodic buffer
- the storage component of the central executive
- a temporary store for information, recording events (episodes) that are happening
- limited capacity of 4 chunks
- links working memory to long-term memory and wider cognitive process such as perception
naturalistic vs controlled
naturalistic - setting where behaviour would usually occur
controlled - structured environment where some variables can be controlled
covert vs overt
covert - ps don’t know they are being observed
overt- ps do know they are being observed
participant vs non-participant
participant - researcher becomes apart of the group being observed
non-participant - researcher remains separate from the group observed
What are examples of cognitive interview techniques
- interview conducted in room of event
- all info described in questions (e.g colour of cars) - may seem irrelevant but can trigger additional memories
- may be asked in a different order; disrupts schemas from filling in gaps of memory
What are examples of misleading information and give a study for each
Describe anxiety in eyewitness testimony and give 2 study examples
Evaluate eyewitness testimony
What are the different explanations for forgetting
- Interference: When new information conflicts with or disrupts existing information, it can lead to interference and make it difficult to retrieve information from memory.
- Decay: Over time, memories fade and become less accessible, leading to forgetting.
- Retrieval Failure: When people are unable to access information from memory, it can be due to a retrieval failure, such as not being able to recall a particular detail from a past event.
- Motivated Forgetting: Sometimes people may intentionally or unintentionally forget information that is emotionally difficult or conflicts with their self-image.
- Context-dependent Forgetting: People may find it difficult to recall information if they are in a different context than when the information was originally learned.
What are the two types of interference