Memory

Research into coding

Research into coding

Baddeley

In STM recall, people did worse on words that sound similar

Short Term coding = Acoustic

In LTM recall, people did worse on words that had similar meanings

Long Term coding = Semantic

How is short term memory coded

Acoustically

How is long term memory coded

Semantically

Capacity research

Initial = Jacobs, found mean 7.3 letter recall, 9.3 number recall

Developed by Miller, STM capacity = 7±2

What is the capacity of STM

7 plus or minus 2

STM Duration research

Peterson and Peterson

PPTs given a trigram, and told to count backwards from a number to prevent rehearsal

Each trial was different lengths (3s, 6s, 9s, 12s)

STM Duration = 18-30 seconds

What is STM duration

18-30 seconds

LTM Duration Research

Bahrick

392 PPTs shown yearbook photos

PT1. Recall from a set of 50 photos

PT2. Free recall

15 years out school = 90% recall

48 years out school = 70% recall

Who identified multi-store model

Atkinson and Shiffrin

3 main parts of multi store model

Sensory register

Short term memory

Long term memory

Sensory Register : What is it

Intakes information

5 stores for 5 sense

Main 2 : Iconic and Echoic (sight and sound)

Sensory register : Duration and Capacity

Duration : <0.5 seconds

Capacity : Massive

evidence of MSM

positive

Baddeley found that words were stored differently in STM and LTM

Different coding for different memory → different stores in brain

evidence of MSM

negative

KF Case Study

Poor recall of numbers when they were READ TO him

Good recall of numbers when HE READ them

Different coding in STM, shows that STM has deeper parts

Who identified the different types of LTM

Tulving in 1985

What are the three types of LTM

Episodic

Semantic

Procedural

Define episodic memory

Recall of events and days

Conscious retrieval e.g. your 17th birthday

Define semantic memory

Knowledge of the world and things, facts

Conscious retrieval e.g. capital of france

Define procedural memory

Memory of how to do things, procedure

Non-deliberate recall e.g. ride a bike

evidence

LTM

positive, tulving

Neuroimaging done by Tulving

PPTs put in a PET scan

Right pre-frontal cortex = Episodic

Left pre-frontal cortex = Semantic

evidence for LTM

positive, cases

HM and Clive Wearing

Damaged episodic memories but working procedural memories

e.g. clive could still play piano

Components in working memory model

central executive

phonological loop

visuo-spatial sketchpad

episodic buffer

Job of central executive

• Is an attention process, so monitors data

• Makes decision and directs slave systems

Job of phonological loop

• Deals with auditory information and preserves order

• Rehearsal of information

Sub-sections of phonological loop

Phonological store = Holds words

Articulatory process = Allow for rehearsal

Job of visuo-spatial sketchpad

• Stores visual and/or spatial information

• 3 or 4 object capacity (Evidenced by Baddeley)

Sub-sections of visuo-spatial sketchpad

Visual cache = Visual data

Inner scribe = arranges data

Job of episodic buffer

• Integrates info from other stores, maintains order of time

• Links working memory to LTM

Evidence for WMM

positive, case

KF

Poor recall when numbers are READ TO him

Good recall when HE READS numbers

• Supports idea of separate stores within stores

Evidence for WMM

positive, DTP

Dual task performance

Baddeley : Found that it was easy to do 1 visual and 1 verbal task, hard to do 2 visual

TIB they use the same slave system at the same time

Types of interference

Proactive interference and retroactive interference

Proactive interference

Old information disrupts the learning of new information

Retroactive interference

New learning disrupts recall of old information

Eval Interference

POS

• Memory and forgetting is tested often in lab experiments

  • Lots of studies = high external validity

NEG

• Artificial situations e.g. memorising consonants, learning lists and numbers

Evidence for interference

Baddeley and Hitch

Asked rugby players to recall names of the teams they played week by week

Evidence showed length after game didn’t matter, how many games they had played in between did

Main reasons for retrieval failure

Encoding specificity principle

Contest- dependant forgetting

State-dependant forgetting

Encoding specificity principle

Discovered by Tulving

If a cue is to be helpful to recall, must be there at learning and at recall

• Mnemonics, music, taste, sound

Context-dependant forgetting

Context around person matches up when learning and recalling e.g. environment

Context-dependant forgetting study

Godden and Baddeley

18 PPTs learning lists of 38 words

When conditions matched up, there was better recall

State-dependant forgetting

Similar to context dependant, but is more about the internal state of the PPT

State dependant forgetting study

Carter and Cassidy

Gave PPTs anti-histamines, made them drowsy

Learnt words drowsy and not drowsy

When mismatch in conditions, recall went down

Eval of Retrieval failure

POS

• Many studies have been done into the area

  • HIGHER VALIDITY

NEG

• Contexts may have to be very different

  • Baddeley argued that of course there would be a difference between land and water, they’re stark different

• Godden and Baddeley’s PPTs were asked if they recognised words, not to actively recall

• ESP isn’t exactly testable

EYEW TEST

Leading Q study

Loftus and Palmer

PPTs watch a video of a car crash and are asked how fast the car was going when it __?

Changing of the verb changed the answer that was given

• Contacted = Mean of 32mph

• Smashed = Mean of 40.5mph

EYEW TEST

Leading Q: Explanations

Response bias: Wording of question influences how a person makes their decision

Substitution : Wording alters memory

EYEW TEST

Post Event Discu: Study

Gabbert et al.

Watch videos of a crime from different perspectives, PPTs studied in pairs and talked before they did a test on what they saw

Control group = 0% mistaken info

PPTs group = 71% mistaken info

EYEW TEST

Post Event Discuss : Explanation

Memory conformity = Go along with each others perceptions

(NSI/ISI?)

EVAL Misleading info EWT

POS

• Real-life applications to police interviews

  • Loftus and Palmer informs police of wording of q’s

NEG

• Artificial = Wouldn’t be watching videos of a crime, alternate emotional state

• Anatasi and Rhodes argued people are more biased to own age when giving eyewitness testimony

  • Younger are more accurate

EYEW TEST

Anxiety → negative study

Johnson and Scott

Johnson and Scott

Procedure

Led PPTs to a waiting room and they hear an argument

High anxiety = Hear glass smash, see man walk out with knife covered in blood

Low anxiety = Man walks out with pen and grease on hands

Johnson and Scott

Findings

PPTS asked to identify man out of 50 pictures

High Anxiety = 33% correct identification

Low anxiety = 49% correct identification

What theory helps explain Johnson and Scott findings

Tunnel theory

• Witness’s attention is drawn to the weapon as it is the source of anxiety

EYEW TEST

Anxiety → Positive study

Yuille and Cutshall

Yuille and Cutshall

Procedure

13 witnesses of shooting and robbery in Vancouver

Interviewed 4-5 months after incident

Asked to recall details and rate how stressed they were + any emotional issues since

Yuille and Cutshall

Little change in 5 months since police interview

High anxiety = 88% accurate recall

Low anxiety = 75% accurate recall

Yerkes-Dodson Law

Also known as inverted-u theory

• There is an optimum level of anxiety

• Too high is just as bad as too low

EYEW TEST

Additional studies for anxiety

Parker et al.

Valentine and Mesout

EYEW TEST

Parker et al.

Hurricane Andrew, interviewed people and judged anxiety by amount of damage done on house

• Medium amount of anxiety = optimum recall

EYEW TEST

Eval Parker et al

Is damage done to property the best way to operationalise anxiety levels

EYEW TEST

Valentine and Mesout

London Dungeons, reduced entrance fee to wear a heart rate monitor

High anxiety PPTS = less accurate details when asked to describe an actor they had encountered

• High anxiety = 17% identified the actor in line-up

• Low anxiety = 75% identified actor in line-up

EYEW TEST

Eval NEG

• Weapon focus (Johnson and Scott) may be based on surprise not anxiety

  • Pickel = Experiment using abnormal hand-held items in hairdressers. Accuracy decreased when item was unusual e.g. raw chicken

• Field studies (Yuille and Cutshall) lack control

  • Post-event discussion, police interviews

  • Extraneous variables

EYEW TEST

4 aspects of cognitive interview (CI)

Report everything

Mental reinstatement

Change perspective

Change order

Rude Men Can’t Cum

EYEW TEST CI

Report everything

Include every detail even if it doesn’t feel relevant

• Trivial details may trigger other important details

EYEW TEST CI

Mental Reinstatement

Such as returning to scene in mind and imagine the circumstances

• Weather, sensory input

  • Context dependant forgetting (Godden and Baddeley)

EYEW TEST CI

Change order

Recall in reverse chronological order or start during middle of event

• Prevents people from reporting what they EXPECT to happen

• Harder to be untruthful

EYEW TEST CI

Change perspective

Imagine themselves in the perspective of another witness or the perpetrator

• Disrupts expectations and schema of the crime

EYEW TEST

Enhanced Cognitive Interview

Forms a deeper relationship between interviewer and interviewee

Witness can talk freely before asked questions

• Encourages open recall

Modified Cognitive Interview

Removes the C’s from RMCC

Suitable for children, stresses relationship and allows witness to control narrative

Studies for CIs

Geiselman et al - CI is more accurate than SPI

Fisher and Geiselman - Amended the CI to form better relationship, ECI

Meta-analysis for CI

Kohnken et al

Memon, Meissner, Fraser

Kohnken et al

• Combined information from over 50 studies

• Found CI’s produce 34% more accurate info

  • Produces more incorrect info

Memon, Meissner, Fraser

• Comparing CI to other methods (ECI, MCI)

• CI produced more accurate detail, more than in Kohnken

  • High amounts of confabulation in MCI

EYEW TEST

Eval NEG CI

• Hard to compare results to SPI, techniques aren’t standardised

• MCI produces more incorrect info

• Takes longer to get witness to calm (time-consuming)

• Training for police officers

EYEW TEST

Eval POS CI

MCI can be used for witnesses who are children/ have learning difficulties

• Application to policing, more practical than SPI

• Both meta-analyses (Kohnken et al, Momen, Meissner, Fraiser) have evidence to show effectiveness