memory AO1

coding

the format in which information is stored in the various memory stores

capacity

the amount of information that can be held in a memory store

duration

length of time that information can be stored in the memory

who conducted research into coding?

Baddely et al

what are the two types of coding?

• acoustic coding

• semantic coding

acoustic coding

coded based on how it sounds

semantic coding

coded based on what it means

Baddely’s research into coding- procedure

tested word recall in different groups with different lists of words immediately (STM) and later on (LTM)

Baddely’s research into coding- findings

• STM was worst when the words sounded similar

• LTM (anything after 30s) was worst when the words meant similar things

Baddely’s research into coding- how is STM coded

acoustically- sound of words is how we remember them

Baddely’s research into coding- how is LTM coded?

semantically- we remember the words by what they mean

who are the two researchers who researched capacity?

• Jacobs

• Miller

Jacobs’ research into capacity of STM- procedure

he used a digit span technique

• reads the digits for the ppts to recall, increasing the digit length until the ppt makes a mistake when recalling the digits

Jacobs’ research into capacity of STM- findings

• average number of digits recalled was 9.3

• average number of letters recalled was 7.3

what did Jacobs conclude the capacity of STM is?

7-9 ish

what did Miller say about the capacity of STM?

it is +-7 (with a range of 2) as all significant things come in 7s

what did Miller say about chunking?

we use it to recall things- it is separating the thing to remember into different sections to memorise

who conducted research into the duration of STM?

Peterson and Peterson

Peterson and Peterson’s research into duration- procedure

• 24 students in 6 trials each

• in each trial, the ppt was given a trigram and a three digit number

• ppt then completes the distractor task of counting back from a number to ensure no mental repetition of the trigram

• ppt told to stop typing after varying times- 3,6,9,12,15 or 18

Peterson and Peterson’s research into duration- findings

• average recall after 3 seconds = 80%

• average recall after 18 seconds = <10%

what did Peterson and Peterson conclude the duration of STM is?

18 seconds without rehearsal

who conducted research into the duration of LTM?

Bahrick

Bahrick’s research into duration- procedure

• 392 American ppts aged 17-74 received high school yearbooks

• condition 1 = a photo recognition test of 50 photos, with some from the ppts yearbooks

• condition 2 = a free recall task where ppts recalled all the names of their graduating class

Bahrick’s research into duration- findings

tested within 15 years of grad = 90% accuracy with photo recognition

tested within 48 years of grad = 70% accuracy for photo recognition

tested within 15 years of grad = 60% accuracy free recalling names

tested within 48 years of grad = 30% accuracy free recalling names

what did Bahrick conclude about the duration of LTM?

it is potentially lifetime

who developed the MSM of memory?

Atkinson and Shiffin

what are the three stages of the MSM of memory?

• sensory register

• STM

• LTM

MSM- sensory register

• takes in stimuli from the environment

• iconic codes images

• echoic codes auditory

duration and capacity of the sensory register

• duration = <0.5 seconds

• capacity = huge

how do you get from the sensory register to the STM?

pay attention

coding, capacity and duration of the STM in the MSM of memory

• coding = acoustic

• capacity = 7-9 +-2

• duration 18 seconds

how do you keep information in the STM?

maintenance rehearsal

how do you get to the LTM from the STM in the MSM of memory?

elaborate or prolonged rehearsal

coding, capacity and duration of LTM in the MSM of memory

• coding = semantic

• capacity = infinite

• duration = potentially lifetime

how do you pull information form the LTM back to the STM?

retrieval

what are the 3 stores of the MSM of memory linked by?

processing

what are the sections of the working memory model?

• central executive

• phonological loop

• visuo-spatial sketchpad

• LTM

working memory model- central executive

• monitors incoming information and either sends it to the PL or the VSS

• capacity = limited

• coding = does not store any information

working memory model- phonological loop

• deals with auditory information and preserves the order the information arrived in

• capacity = around 2 seconds

• coding = acoustic

working memory model- visuo-spatial sketchpad

• stores visual/spatial information which is then broken down into the inner cache and the inner scribe

• capacity = around 3-4 objects

• coding = semantic

working memory model- episodic buffer

• temporarily stores information for the central executive, it integrates information and keeps it in order

• capacity = around 4 chunks

• coding = not limited to one way of coding

what are the 2 explanations for forgetting?

• interference

• retrieval failure

what is interference?

when two pieces of information conflict with each other, resulting in forgetting one or both

is interference an explanation for forgetting in LTM or STM?

LTM- we can’t access the information even though it is available

proactive interference

older memory interfering with a newer one

retroactive interference

newer memory interfering with an older memory

Baddeley and Hitch’s research into interference- procedure

• asked rugby players to recall the names of the teams they played against in rugby season

• the players all played for the same time interval, but the number of games varied due to missed matches because of injury

Baddeley and Hitch’s research into interference- findings

players who played the most games had the poorest recall (most interference for memory)

Baddeley and Hitch’s research into interference- conclusion

interference can operate in real world situations

what is retrieval failure sometimes known as?

cue dependent forgetting

what is retrieval failure explained by?

the encoding specificity principle

what is the encoding specificity principle?

states that if a cue is to help us recall information it has to be present at encoding and retrieval

what is retrieval failure?

forgetting due to a lack of cues

internal cues

state dependent cues e.g. mood state

external cues

context dependent cues e.g. temperature and smell

is retrieval failure an explanation for forgetting in LTM or STM?

LTM

Godden and Baddeley’s study into context-dependent cues- procedure

• divers learnt a list of words either on land or underwater

• 4 conditions- land and land, underwater and underwater, underwater and land, land and underwater

Godden and Baddeley’s study into context-dependent cues- findings and conclusions

• accurate recall was 40% lower in the non-matching conditions

• this is because the external cues present at encoding were different to those cues at recall

Godden and Baddeley’s study into context-dependent cues- procedure

• created different psychological states with antihistamines used as mild sedatives

• 4 conditions- on drug and not on drug, on drug and on drug, not on drug and on drug, not on drug and not on drug

Godden and Baddeley’s study into context-dependent cues- findings and conclusions

conditions with a mismatch of the internal state had worse performance on the memory test- state dependent cues are absent = more forgetting

EWT- what do leading questions effect?

the accuracy of recall

EWT- what are the 2 ways leading questions effect EWT?

• response bias- doesn’t effect memory, just effects the answer given

• substitution- actually distorts the memory as well as changing the answer

Loftus and Palmer’s research into leading questions- procedure

• 45 students watched clips of car accidents

• then asked how fast the car was going when it…

• said either- hit, contacted, smashed, collided, bumped

• this was the critical question

Loftus and Palmer’s research into leading questions- findings

• average speed guessed for ‘contacted’ = 31.8 mph

• average speed guessed for ‘smashed’ = 40.5 mph

Loftus and Palmer’s research into leading questions- conclusions

the verb used affected the answer- EWT can be affected by leading questions

Loftus and Palmer’s follow up research into leading questions- procedure

asked ppts a week later ‘did you see broken glass?’

Loftus and Palmer’s follow up research into leading questions- findings

ppts were more likely to answer yes if they were in the ‘smashed’ condition even though there was no glass in the video

Loftus and Palmer’s follow up research into leading questions- conclusions

memory is affected by leading questions- supports the substitution explanation

what is post-event discussion?

eyewitnesses to a crime discussing their experiences and memories with eachother

why does post-event discussion affect EWT?

• memory contamination- combining (mis)information from other witnesses with their own memories

• memory conformity- witnesses go along with each other for social approval or because they think they must be wrong

Gabbart’s research into post-event discussion- procedure

• 60 students and 60 older adults

• ppts studies in pairs

• each ppt watched a video of the same crime, but from a different perspective, meaning that each ppt could see features that another ppt couldn’t

• both ppts discussed what they had seen before individually completing a memory test

Gabbart’s research into post-event discussion- findings

71% of ppts mistakenly recalled aspects that they had not seen but had discussed with other ppts- in a control group with no discussion, this was 0%

Gabbart’s research into post-event discussion- conclusions

evidence supporting memory conformity affecting EWT

what is anxiety?

a state of emotional and physical arousal and is a normal reaction to stressful situation

it can be argued that anxiety has both a ______ affect on EWT

positive and negative

why does anxiety make recall worse?

it creates physiological arousal in the body that prevents us from paying attention to important cues, so recall is worse

what does anxiety focus the witness on?

central details of the attack e.g. the weapon

what is the focus on central details of the attack called?

weapon focus

Johnson and Scott’s research into the negative effect of anxiety on EWT- procedure

• ppts are in a waiting room

• high anxiety condition- heard argument and breaking glass then saw a man walk past holding a bloody knife

• low anxiety condition- heard a casual conversation then saw a man walk past holding a pen with grease on his hands

• after this ppts had to identify the pan from 50 photos

Johnson and Scott’s research into the negative effect of anxiety on EWT- findings

• 49% accuracy in pen condition

• 33% accuracy in knife condition

Johnson and Scott’s research into the negative effect of anxiety on EWT- conclusions

high anxiety reduces accuracy of EWT- this can be explained by weapon focus

why does anxiety have a positive effect on EWT?

the stress creates physiological arousal which triggers the fight or flight response, increasing our alertness and improving our memory as we become more aware of the cues in the situation

Yuille and Cutshall’s research into the positive effect of anxiety on EWT- procedure

• after a real life shooting

• witnesses were reinterviewed 4-5 months after the shooting and asked to rate their stress at the time of the shooting and to recall the details of the shooting (accuracy was determined by how many details were provided)

Yuille and Cutshall’s research into the positive effect of anxiety on EWT- findings

ppts recording higher stress levels had better recall

88% accuracy = most stressed vs 75% accuracy = least stressed

Yuille and Cutshall’s research into the positive effect of anxiety on EWT- conclusions

anxiety improves the accuracy of EWT in real-world situations

overall, the research has shown that…

high levels of stress can have a negative impact on the accuracy of EWT, but it may also increase accuracy of memory

this contradiction is best explained by the…

Yerkes-Dodson law

what does the Yerkes-Dodson law say?

accuracy is better under moderate conditions of arousal- a small/medium increase in arousal may increase the accuracy of memory, but low or high levels interfere with accuracy

overall, EWT can be…

both positively and negatively affected by anxiety