Memory Flashcards
Discuss the coding, capacity and duration of LTM and STM (16 marks)
A01
Coding:
Baddeley
4 groups
Acoustically similar and disimilar
Semantically similar and dissimilar
Findings showed
STM = acoustically coded
LTM = semantically coded
A03:
+ shows separate memory stores
- artificial stimuli rather than meaningful material - limited application
Capacity:
Jacobs
mean digit span = 9.3 items
mean letter span = 7.3 items
Miller
STM capacity = 7 +- 2
Chunking = group sets of digits or letters into units or chunks
A03:
+ valid study - Jacob’s study can be replicated
- Overestimated STM capacity - Cowan reviewed and found 4 chunks plus or minus 1 (not 7)
Duration:
Peterson and Peterson
24 students
given a consonant syllable (YCG) and 3 digit number (769)
counted backwards to prevent mental rehearsal
had to stop after varying periods of time: 3,6,9,12,15,18
Findings:
3 seconds = 80% recall
18 seconds = 3% recall
Suggests STM is 18 seconds
Bahrick
392 American participants 17-74 age
1st condition= 50 photos from high school yearbook
2nd condition = free recall naming all people from their graduating class
Findings
within 15 years of graduating = 90% accurate photo recognition
After 48 years = 70% photo recognition
15 years = 60% free recall
48 years = 30%
Shows LTM may last up to a lifetime
A03:
- meaningless stimuli in the Peterson and Peterson’s study - lacks external validity
+ high external validity - Bahrick’s study tests meaningful memories which makes it more of a ‘real’ estimate
Discuss the multistage model of memory (16 marks)
A01
Atkinson and Shiffrin
- Sensory register - iconic, echoic
- Short term memory - acoustically
- Long term memory - semantically
SR = high capacity, short duration
STM requires = maintenance rehearsal
LTM requires = retrieval
Study:
HM - hippocampus accidentally removed when trying to relieve epilepsy = could not form new long term memories
however, performed well on immediate memory span - STM
Shows two separate stores for STM and LTM
A03
+ research support from Baddeley = we mix similar sounding words in STM but similar meaning in LTM
Shows STM and LTM are independent, different stores
- many of the supporting studies use artificial material
- more than one STM store = KF had amnesia and could recall information when he read digits to himself but could not when they were read out loud to him
Potential STM for nonverbal sounds - prolonged rehearsal not needed to transfer to LTM = Craik and Watkins found type is more important than amount
Elaborative rehearsal may be more important = link to existing knowledge - MSM is oversimplified = data used now out of date
Discuss types of long term memory (16 marks)
A01
Types:
Episodic = ability to recall events from our lives (requires conscious effort) (time stamped)
Semantic = contains our shared knowledge of the world (not time stamped) (requires conscious effort)
Procedural = our memory for actions or skills (how we do things) (not time stamped) (no conscious effort needed)
A03
+ clinical evidence = HM and Clive Wearing episodic damaged in both but semantic and procedural relatively unaffected
+ Supports tulving’s view that there are different memory stores in the LTM
+ real world application - can help psychologists reduce effects of memory
- conflicting neuroimaging evidence = which sides of the brain are semantic and episodic memory (Peterson and Tulving)
- Peterson = S = Left and E = Right (of prefrontal cortex)
- Tulving = E = Left and S = Right (of prefrontal cortex)
Discuss the working model of memory (16 marks)
A01:
Baddeley and Hitch
explains how one aspect of memory (STM) is organised and how it functions
Central Executive:
- supervisory role
- allocates slave systems
- limited capacity, does not store information
Phonological loop:
- acoustically coded
- deals with auditory information and preserves order it arrives
- phonological store = stores words you head
- articulatory processes = allows maintenance rehearsal (capacity of this ‘loop’ is two seconds worth of words you can say)
Visuo-spatial sketchpad:
- stores visual and/or spatial information when required
- the visual cache = stores visual data
- the inner scribe = records the arrangement of objects in the visual field
Episodic Buffer:
- temporary store for information, integrating the visual, spatial and verbal information
- records events and their order = seen as a storage component of the central executive
- limited capacity = 4 chunks (Baddeley)
- links working memory to long term memory and wider cognitive processes such as perception
A03:
+ clinical evidence = KF bad auditory good visual, shows they are separate stores, phonological damage, visual spatial in tact
+ dual task performance (Baddeley) = performance on visual and verbal task was normal but on two visual or verbal tasks performance decreased - compete for same slave system, shows there are separate slave systems
- nature of the central executive = lack of clarity, “most important, least understood” (Baddeley), challenges integrity of the model
- validity of the model = carried out in lab conditions and many studies don’t use everyday tasks
Discuss interference theory as an explanation for forgetting (16 marks)
A01
Types:
Proactive interference = old displace new
Retroactive interference = new displace old
Study:
McGeoch and Mcdonald
had to learn original list till 100% accuracy
6 lists of a different set of 10 words
had to learn until 100% accuracy
Findings:
most similar material to original list = worst recall
Shows interference is strongest when memories are similar
Explanation:
PI = previously stored information makes new information more difficult to store
RI = new information overwrites previous similar memories because of the similarity
A03:
+ Real-word application, Baddeley and Hitch = asked rugby players to name teams they played, more games = worse recall
- interference is temporary = can be overcome with cues, shows that interference causes a temporary loss of accessibility to material that is still in LTM, a finding not predicted by interference theory
- validity issues = most of the studies supporting interference are lab based so researchers have control over variables, artificial material, unrealistic procedures, in everyday life we often learn something and recall it much later
- A more likley explanation for forgetting in everyday life is due to retireval failure (a lack of cues)
+ support from drug studies = retrograde facilitation
Discuss retrieval failure as an explanation for forgetting (16 marks)
A01
Encoding specificity principle = if cue is going to be helpful it has to be present at the time of encoding (when we learn the material) and present at retrieval (when we are recalling it), if not there will be forgetting
Context dependent forgetting = recall depends on external cue (e.g weather or a place)
Study:
Godden and Baddeley (1975)
deep sea divers
learn a list of words underwater or on land and then recall underwater or on land
this created 4 conditions:
- learn land - recall land
- learn land - recall underwater
- learn underwater - recall land
- recall underwater - recall underwater
Findings:
2 conditions recall and learning contexts matched
accurate recall 40% lower in non matching conditions
retrieval failure due to different external cues available at learning and at recall
State dependent forgetting = recall depends on internal cue (e.g feeling upset, being drunk)
Study:
Carter and Cassaday (1998)
antihistamine drugs (participants slightly drowsy)
creates an internal psychological state different to normal
learn list of words/passages and prose and then recall
four conditions:
- learn on drug - recall on drug
- learn on drug - recall not on drug
- learn not on drug - recall on drug
- learn not on drug - recall not on drug
Findings:
- mismatch between internal state at learning and recall = performance on memory test was worse
shows when cues absent = more forgetting
A03:
+ real world application = we use cues in everyday life such as going back to another room to remember what you were thinking - context dependent forgetting
+ research support = Godden and Baddeley and Carter and Cassaday
- recall vs recognition = Godden and Baddeley re did their study but using recognition rather than recall (say whether they recognised a word read to them from a list) = performance was the same in all 4 conditions (no context dependent effect)
Retrieval failure is a limited explanation - only applies when recalling info not recognising it - problem with the ESP = impossible to establish whether cues have been encoded or not - based on assumptions
Discuss misleading information in eye-witness testimony (16 marks)
A01
Leading questions = may pressure into giving certain answer/response
Study:
Loftus and Palmer (1974)
45 participants
watch car crash clip
asked “how fast were the cars going when they hit each other?”
five groups - each given a different verb, (hit, contacted, bumped, collided, smashed)
Findings:
mean speed calculated for each group
contacted = 31.8mph
smashed = 40.5mph
leading question biased the eyewitness’s recall of the event
Why:
no effect on memories but on how they decide to answer
follow up study (same people) to support the substitute explanation (proposes the word used changes the memory)
smashed = more likely to report glass (there was none)
hit = no glass
verb altered their memory
Post event discussion:
eyewitnesses may discuss a crime and experiences
Study:
Fiona Gabbert (2003)
watched same clip from different pov (saw elements partner did not)
both then discusses before individually completing test of recall
Findings:
71% mistakenly recalled aspects they did not see but heard in discussion
control group where there was no discussion = 0%
Evidence of memory conformity
Why:
memory contamination = post event discussion can alter/distort eyewitness testimonies - combine information from other witnesses with their own memories
Memory conformity = witnesses go along with each other, either to win social approval (NSI) or because they believe the other witnesses are right and they are wrong (ISI) - unlike memory contamination, the actual memory is unchanged
A03
+ Real world application = practical use in justice system - psychologists asked to explain the limits of EWT to juries
shows it can help to improve the way the legal system works = protect innocent people from faulty convictions based on unreliable EWT
- Artificial study = lab study - answers don’t have consequences (less motive to be accurate)
- evidence challenging memory conformity = Skagerberg and Wright - showed participants clip of mugger with two versions (light brown hair, dark brown hair), participants discussed clips after seeing different versions and often reported a ‘blend’ of the two
Suggests memory is distorted through contamination rather than memory conformity - demand characteristics = lab study can cause misleading information as participants want to be helpful so they guess when asked a question they don’t know the answer to
Discuss anxiety in eye-witness testimony (16 marks)
A01
Anxiety = negative effect on recall due to weapon focus
Study:
- Johnson and Scott (1976)
- Low anxiety condition - casual conversation = man walked out with greasy pen
- High anxiety condition - heated argument, sound of breaking glass = man walked out with bloody knife
Findings:
participants picked out man from 50 photos
49% accurate = pen condition
33% accurate = knife condition
tunnel theory = only remember central events (weapon focus)
Anxiety = positive effect on recall (fight or flight increases alertness)
Study:
Yuille and Cutshall (1986)
shooting in Vancouver, Canada
shop owner shot thief dead
21 witnesses - 13 took part in study
interviewed 4/5 months after - compared to police interviews at the time of the shooting
accuracy determined by number of details reported in each account
witnesses asked about stress at the time (7 point scale)
asked if they had emotional problems (sleeplessness) since the event
Findings:
very accurate - little change in amount recalled (though some details less accurate e.g colour of items, age, weight, height)
those who reported highest stress levels were the most accurate = 88% compared to 75% for less stressed group
suggests anxiety doesn’t have a detrimental effect on accuracy of EWT memory in a real world context (may even enhance it)
Explaining contradictory findings:
Yerkes and Dodson
Inverted U
emotional and physical arousal
low arousal = low accuracy
high arousal = high accuracy
however, optimal level of arousal = highest accuracy
too high arousal = recall suffers a drastic decline
A03
- Unusualness not anxiety = Pickel conducted experiment using scissors, handgun, a wallet or a raw chicken as hand held items in a hairdressing salon video (scissors = high anxiety, low unusualness)
EW accuracy was poorer in the high unusualness conditions (chicken and handgun)
weapon focus is due to unusualness rather than anxiety - tells us nothing about the effects of anxiety on EWT
- problems with the ‘inverted U’ theory = it ignores the fact that anxiety has many elements (cognitive, behavioural, emotional, physical) - only focuses on physical arousal and assumes the is the only aspect linked to EWT - the way we think (cognitive) may be more important
MORE EVAL POINTS NEEDED
Discuss the cognitive interview as a way of improving EWT (16 marks)
A01
FIsher and Geiselman (1992) argued EWT could be improved if the police used better techniques
Cognitive interview:
1. Report everything - include every single event even if it seems irrelevant - may trigger other memories
2. Reinstate the context - return to original crime scene ‘in their mind’ and imagine the environment (context dependent forgetting)
3. Reverse the order - events recalled in different order from the original sequence = prevents people reporting expectations of how it must have happened and prevents dishonesty
4. Change perspective - recall incident from other peoples perspective = disrupt schema which produces expectations
The enhanced cognitive interview:
Fischer (1987) added elements to the CI - focuses on social dynamics of the interaction
ideas included = reduce EW anxiety, minimising distractions, getting witness to speak slowly, ask open ended questions
A03
+ Supporting research = Kohnken, meta analysis of 55 studies comparing cognitive interview with standard police interview - found an increase of 41% in accurate information
- However, also found an increase in the amount of inaccurate information recalled
- some elements more useful = Bull and Milne (2002) found ‘report everything’ and ‘reinstate the context’ produced the best recall
- CI is time consuming = police officers need to be specialist trained - costly
Variations of the CI
