Memory:

Key:= Baddiel + Bradley

(bear) = Baddeley

= H.M (Study by Milner 1966)

= Duration of LTM by Bahrick et al 1975

= Miller’s magic no. 7 (1956)

= Baddeley and Hitch 1974 Working Memory Model

= Eye witness testimonies – L(1979), Y/C, C/H(1993)

= Negative impacts of Anxiety & EWT, Loftus 1979

= Positive impacts of anxiety & EWT, Christianson & Hubinette (1993)

Multi-store model – Atkinson and Shiffrin (1968):

Multi-store model of memory evaluation:

• Distinguishes a difference between the capacity and duration of STM and LTM.

• Simplistic – explains something complex in a very simple manner.

• Focuses too much on the structure of the model as opposed to the processes involved.

• ‘rehearsal’ is deemed the only way to move information from STM to LTM – maybe there’s another way.

Milner (1966) – H.M.

• Supports the MSM – as it shows that the LTM and STM are stored differently.

• Had brain surgery, which left him unable to recall things that had just happened.

• It was concluded that he couldn’t move memories into his long term memory.

Short Term memory…

Capacity of STM by Baddeley et al (1975):

Aim: To see if more people could remember more short words than long words in a serial recall test. So demonstrating that pronunciation times rather than the no. of items to be recalled determines the capacity of STM.

Procedure: - reading speed of ppt was measured- given 5 words on a screen- One set one-syllable words, one set multi-syllable words- Ppts were asked to write down 5 words in order immediately after presentation

Findings:- More short words were recalled than long words- Able to recall as many words as they could say in 2seconds- Strong + correlation between reading speed & memory spanConclusion: Immediate memory span represents the no. of items of whatever

length can be articulated in 2 seconds.

Duration of STM: Peterson & Peterson (1959)

Aim: To see how long STM lasts when rehearsal is preventedProcedure: - Ppts were briefly showed 3 letters (trigram)- Ppts were asked to count backwards to stop them rehearsing

the letters- After 3, 6, 9, 12, 15 and 18 seconds, they were asked to recall

the original 3 letters (in order)Findings:- 80% of trigrams (3 letters) were recalled after 3s- By 18s, less than 10% of trigrams could be recalledConclusion: When rehearsal is prevented, short term memory doesn’t last long

Encoding in STM: Baddeley (1966)

Aim: To explore the effects of acoustic & semantic encoding in STMProcedure: ppts divided into 4 groups, ones that heard:1. Acoustically similar words (map/mad/man)2. Acoustically dissimilar words (pen/day/few)3. Semantically similar words (big/large/grand)4. Semantically dissimilar words (hot/old/late) Findings: - 55% A.S. words were recalled- 75% of A.D words were recalled- Semantics (meaning) were similarConclusion:STM relies more on acoustics than their meaning

Long term memory…

Duration of LTM: Bahrick et al (1975):

Aim: To establish the existence of very LTM, seeing whether there’s a difference between recognition and recall.

Procedure: - investigators found old high school grads. Over 50-year period. IN AMERICA.- 392 grads. Were shown yearbook photos- 1 group – recalled names from memory (recall)- 2nd group – matched names to faces (recog.)

Findings:- Recall group: After 47 years, less than 20% accuracy- Recog. Group: After 47 years, accuracy @ 60%Conclusion:- People can remember certain types of info. For almost a lifetime- Long term memory is better in recog. than recall.

Encoding in LTM: Baddeley (1966)

Aim: To explore the effects of acoustic & semantic coding on LTMProcedure: ppts divided into 4 groups…1. Acoustically similar words (map/mad/man)2. Acoustically dissimilar words (pen/day/few)3. Semantically similar words (big/large/grand)4. Semantically dissimilar words (hot/old/late) - After 20 minutes, they were given another task to do, before having to

recall the words.Findings:- Recall 55% accuracy for S.S words- Recall 85% accuracy for S.D words- Recall was same for A.S and A.DConclusion:LTM is primarily semantically coded (opposite to STM!)

Miller’s magic number 7 (1956):

Miller found that people had a digit span of 7±2

Working Memory Model: Baddeley and Hitch

(1974)

Visual Episodic Language

Long term memory

Working Memory Model: Baddeley and

Hitch (1974)Central executive: Most important. Involved in decision making, and

problem solving. Flexible, and can process lots of informationLimited storage capacityPhonological loop:‘Inner ear’ – holds acoustic info. and ‘inner voice’ –

allows sub vocal repetition (by getting a ppt to say ‘the the the’ during a memory task prevents the phonological loop from working)

Visuo-spatial scratch pad:‘inner eye’, stores visual and spatial info.Sets up and manipulates mental images.Limited capacityLimits of the systems are independent(added in 2000) Episodic Buffer:Integrates information from different sources Limited capacity

Working Memory Model: Baddeley and

Hitch (1974)

Working Memory Model: Baddeley and

Hitch (1974)• Evidence to support

phonological loop (Baddeley 1975 – investigating the ‘word-length effect’)

• Evidence to support visuo-spatial scratch pad (Baddeley 1973 – ppts had to do a tracking task along side a letter imagery task, which they found difficult, proving the visuo-spatial is processed separately)

• Not much is known about the central executive

Eye-witness testimony (EWT):

‘An area of memory that investigates the accuracy of memory following an incident, and the type of errors that are commonly made in that situation’

Negative impacts of Anxiety and EWT: Loftus (1979)

Aim: To find out if anxiety during a witnessed incident affects the accuracy of later identification.

Procedure: Ppts were split into 2 groups:1. A low key discussion was overheard followed by a person coming out of the

lab with a pen, and grease on their hands.2. A noisy hostile exchange was overheard followed by a person emerging from

the lab with a paper knife covered in blood.Ppts in each situation were asked to identify the person who had emerged from

a line-up of 50 people.Findings: 1) The group that had sit. 1) were accurate 49% of the time 2) The group that had sit. 2) were accurate 33% of the timeConclusion:Ppts were too focused on the weapon to notice the person’s face.

• Interviewed 13 real-life witnesses, who’d seen a shooting

• Some witnesses were closer than othersInterviews showed that:- Witnesses gave accurate accounts several months later- Those closest to the shooting provided the most detail- Misleading questions had no effect on accuracy- Those who were most stressed provided the most

detailed accounts

Positive impacts of Anxiety and EWT: Yuille and Cutshall

• Questioned 110 witnesses, who had (between them) witnessed 22 genuine bank robberies.

• Witnesses who were more accurate, were bystanders (not threatened themselves)

• Their recall continued to be better, even after a 15 month period.

Positive impacts of Anxiety and EWT: Christianson and

Hubinette (1993)

Children and EWT Ceci & Bruck (1993):

Repeated questions – Young children are more likely to change their answers when asked a second time.

Encouragement to imagine – Young children are more likely to make up details.

Peer pressure – If a child feels pressured, it may affect their answers

Authority figures – Children may be more susceptible to misleading info. due to desire to please authority figures.

Leading questions:

‘Questions which are worded in such a way that they might make someone answer in a particular way’

- They’ve been found to affect EWT as they cause a bias in the answers.

Leading questions – Loftus (1974)

Aim: Seeing if leading questions distorted the accuracy of EWT.Procedure: 45 students watched a series of short traffic accidents,

and given a questionnaire after each one. Within each questionnaire, there was one ‘critical question’, which was ‘How fast were the cars going when they ____ eachother?’

Findings: Verb Average estimated speed

Smashed 41

Collided 40

Bumped 38

Hit 34

Contacted 31

Misleading info.:

Misleading info: The investigator slipping in words that wrongly implicate that something happened, when it didn’t.

Often, it makes a change in the ppts memory.

Misleading information – Loftus (1975) Barn

• 150 ppts a car accident• Divided into two groups• 1st group: Asked 10 questions that were consistent with the

film.• 2nd group: Asked 9 questions that were consistent, and one

question that was misleading: ‘How was was the sports car going when it went past the barn’ (there was no barn!)

• One week later… Ppts were asked ‘did you see a barn?’• 1st group: 2.7% said yes• 2nd group: 17.3% said yes• Loftus concluded that the barn was added to their memories

from due to the information from the misleading questions.

Cognitive Interviews – Geiselman et al (1985):

• 4 techniques: 1. Context reinstatement – weather, smells.2. Reverse order.3. Detail – report everything.4. Change of perspective.• Good search to support it (Geiselman 1988)• Officers would have to be re-trained which

would be time consuming and costly.

CORP =contextorderreport

perspective

Cog. Interview – Geiselman (1988)‘effectiveness of CIT in lab setting’

• 89 students shown crime video.• Some interviewed with Standard Interview, some by

CIT.• Those interviewed by CIT showed higher recall than

those interviewed with Standard Interview.• Lab study• Ecological validity – low, due to being shown a video

of a crime. Wouldn’t necessarily work IRL settings.• All the people shown were students. Therefore not

representative of the whole popualation.

Cog. Interview – Fisher et al (1989)

‘effectiveness of CIT in real-life setting’

• Detectives, Florida, USA, trained in CIT. • 47% increase in info. Produced by witnesses

compared to pre-training.• CIT produces more information than Standard

Interview.• Ecologically valid – uses real life settings.• Ethnocentric – All from Florida.

Improving memory:

1. Organisation hierarchies

2. Encoding specificity principle

3. Using mnemonics - inc. Method of Loci.

Organisation hierarchies:

I’m in my HOUSE – which is in NORWICH – Which is in ENGLAND – which is part of GREAT BRITAIN

Evidence:Bower et al (1969) -Learnt words-1st group used hierarchy technique = 65% of words correct-2nd group didn’t use hierarchy technique = 19% words correct

Internally valid – extraneous variables were controlled as it was a LAB STUDYNot real life situation – may lack ecological validity

Encoding Specificity Principle – Tulving and Thompson (1973):

• When we learn things, we encode them with links to the context in which we learnt them.

• The context is classed as a ‘retrieval cue’ which helps to recall information stored in LTM.

• This may explain why our recognition is better than our recall memory

Using mnemonics:

‘Techniques for improving memory based on encoding information in special ways so that a strong memory trace is established along with effective cues’

E.g. ‘Richard Of York Gave Battle In Vain’ ‘Dear Keith Please Could Our Family Go Somewhere’

Method of loci:

• Assigns aspects of info. to familiar images in a sequence.

Evidence: Paivio 1971 - He suggested that words & images were processed separately.

- Meaning they are ‘double encoded’, therefore deeper level of processing

Learning and retrieval – Godden and Baddeley

Aim: To investigate the relationship between learning and retrieval environments

Procedure: Divers were given 40 unrelated words, either on land, or 15 feet under water.Half of the divers switched environments before they tried to recall the words

Findings: The divers that learned and recalled in the same situation remembered the most words

Conclusion: The divers benefitted from recalling in the same environment as it held ‘retrieval cues’