Memory

What is Short Term Memory (STM)

-Limited capacity memory

-Acoustic Coding

-capacity between 5 and 9 items

-duration about 18 secs

What is Long Term Memory (LTM)

-Permanent memory store

-Coding is semantically

-Infinite capacity

-duration= lifetime

What is coding

Information that we store that has to be written in memory in code

What is Baddleys procedure

Gave different lists of words for 4groups of participants to remember: Acoustically similar or dissimilar words, Semantically similar or dissimilar words

What was Baddelys findings

Information is coded acoustically in STM and semantically in LTM. Immediate recall was worse with acoustically similar words. Recall after 20 mins was worse with semantically similar words

What is Capacity

Concerns how much data can be held in a memory store. LTM has a potentially unlimited capacity.

Joseph Jacobs Procedure

Measured a digit span by reading out 4 digit numbers and the participants had to recall the out loud in correct order. Researcher then reads out 5 digits until participant can’t recall order correctly

Joseph Jacob’s Findings

Mean was 9.3 digits and 7.3 for letters.

Miller thought spam if STM is about 7 items +- 2 chunks of information

Margret and Lloyd Peterson procedure

Gave 24 students constant trigrams to remember and were also given a 3 digit number to count back from

The retention of the interval was varied 3,6,9,13,18 seconds

Margret and Lloyd Petersons Findings

After 3 seconds recall was 90%, after 18 seconds recall was 3%

How long is the STM

About 18 seconds unless we repeat information

What was Bahrick et als procedure

Studied 392 american participants 17- 74. Recall was tested through a photo recognition test consisting 50 photos some from their high school.Or free recall were participants recalled all the names of their graduating class

Bahrick et als Findings Photo recognition

• 90% accurate after 15 years

• 70% accurate after 48 years old

Bahricks et als findings free recall test

• 60% accurate after 15 years old

• 30% accurate after 48 years old

What is STMs duration

Up to a lifetime for some material

Strengths of Short and Long term memory

- Baddeleys coding study is generalisable: 72 participants

- Chunks matter in capacity: Simon (1974) found. people have smaller memory span for larger chunks

- Bahri et als duration study has high external validity: meaningless pictures meant recall was low

Limitations of Short and Long Term Memory

- STM may not be coded exclusively acoustic. Brandimote et al found participants used visual coding in STM when given pictures to remember and prevented verbal rehearsal

-Miller may overestimate capacity. Cowan (2001) also researched STM. He concluded STM was only 4 chunks

-Peterson and Peterosns duration study has low external validity. Recall if constant syllables does not reflect everyday life

What is the Multistore Model (MSM)

A representation of how memory works in terms of 3 stores called: sensory memory, short term memory and long term memory. It also describes how information is transferred from one another, what makes some memories last and disappear

What happens in sensory memory

-All stimuli from environment is padded into sensory memory register

-Capacity is large but duration is limited(ms)

-Transfer from SM to STM happens when there’s attention

What happens in STM

-limited capacity, coded acoustically, duration 18 seconds

-Transfer from STM to LTM is through rehearsal

What happens in LTM

-Pernament memory store

-Coded semantically

-lifetime duration

-unlimited capacity

-Transfer from LTM to STM though retrieval

Strengths of MSM

-Peterson + Peterson controlled lab experiments support existence of STM and LTM, Beardsley found prefrontal cortex is active during STM but not LYM. Squire found the opposite

-Support from case studies: HMs brain damage was caused from having hippocampus removed. He could not form new LTM

Limitations of MSM

MSM overly simplistic. Baddelyes and Hitch (1974) suggest LTM is divided into a number of qualitatively different stores

What is Episodic Memory

A long term memory store for personal events. It includes memories of when the events occurred and of the people, objects, places and behaviours involved. Memories from this store have to be retrieved consciously with effort

What is Semantic Memory

A long term memory store for our knowledge of the world. This includes facts and our knowledge of what words and concepts mean. These memories usually also need to be recalled deliberately

What is Procedural Memory

A long term memory store for our knowledge of how to do things. This includes our memories of learned skills. We usually recall these memories without making a conscious or deliberate effort

Tulving (1985) discovery

realise MSM is overly simplistic

Strengths of Types Of Long Term Memory

-Case study evidence: Clinical studies of amnesia (HM+ Clive Wearing)Showed difficulty recalling events from the last but semantic memories were in tact (HM didn’t need concept of dog explained) and procedural memory also intact (Clive could still play piano)

-Practical Applications helping people with Memory Problems:Belleville et al(2006) devised an intervention for older people targeting their episodic memory, improved memory compared to a control group

Types of Long Term Memory

• Episodic

• Semantic

• Procedural

Limitations of Types of Long Term Memory

Problems from patients with brain damage- difficult to conclude patients such as Hms exact part of the brain that are affected until patient has died

What is the Working Memory Model (WMM)

A representation of STM. The model acts as an explanation of the memory used when working on a task. Each store/component is qualitatively different

What is the Central Executives Main purpose

Supervisory role- monitors upcoming data, directs attention and allocates subsystems to tasks

Central Executives Capacity

Very Limited

Central Executives coding

It can code any types of information (sight, sound, smell, taste, touch)

Phonological Loops Main Purpose

Deals with Auditory information (ie coding is acoustic) and preserves the order in which information arrives. Divided into:

-Phonological store: Words you hear

-Articulatory Process: Allows maintenance rehearsal

Phonological Loops Capacity

2 seconds worth of information

Phonological Loops Coding

Acoustic

Visuospatial Sketchpads Main Purpose

To visualise (eg. If you are asked to work out how many windows there are in your house). Divided into

-The visual cache; which stores visual data

-The Inner Scribe; records arrangement of objects to visual feild

Visuospatial Sketchpads Capacity

Limited according to Baddeley is 3-4 objects

Visuospatial Sketchpads Coding

Visual and/ or spatial information when required

Episodic Buffers Main Purpose

General store for visual and acoustic information. Integrates information from central executive, phonological loop and visuospatial sketchpad

Episodic Buffers Capacity

limited capacity of 4 chunks

Episodic Buffers Coding

Codes information from all senses

Strengths of Working Memory Model

-Shallice + Warrington (1970) studies KF who had a brain injury. His STM for auditory information was poor but could process visual information normally

-Dual Task Performance Studies Studies: Baddeleys participants found it harder to carry out 2 visual tasks at the same time than do a verbal and visual task this is because there are different subsystems for audio and visual input

Limitations of WMM

- Problems using case studies. Difficult to generalise whole population with people with brain injury

What is Interference

Forgetting because one memory blocks another, causing one or both memories to be distorted or forgotten. This is most likely to occur when 2 memories are similar

What is Proactive Interference

An older information interferes with new

What is Retroactive Interference

New interferes with old

When is interference worse

when memories are similar

McGeoch and McDonalds effects of similarity Procedure

Participants asked to learn a list of words to 100% accuracy. They were then given a new list to learn. The new material varied in the degree which it was similar to the old

Mcgeoch and McDonalds Effects of similarity Findings

The most similar material (synonyms) produced the worst recall

Group of words participants had to learn

Group 1: Synonyms

Group 2: Antonyms

Group 3: unrelated words

Group 4:consonant syllables

Group 5: 3 digit numbers

Group 6: No new list

Strengths of Explanations for Forgetting Interference

-Supporting Evidence: Baddely and Hitch asked rugby players to recall names of teams they’d played this season. Those who played the most games had the worst recall- High external validity

Real world applications: In advertising Danaher et al found that both recall and recognition of an advert was impaired when participants were exposed to two ads competing for a product

Limitations of explanations for forgetting: Interference

- Only explains so instances- Only happens when 2 memories are quite similar which doesn’t happen all the time- this means that other explanations may be better in some situations

Loftus + Palmer Leading questions procedure

45 students were shown 7 films of different traffic accidents. After participants were given a questionnaire with key question ‘How fast were the cars going when they ____ each other’

In the Leading Questions procedure what were the different words?

-Smashed

-Hit

-Collided

-Bumped

-Contact

Loftus and Palmer Leading questions Findings

-Smashed: 40.8 mph

-Collided: 39

-Bumped: 38

-hit: 34

-Contact: 31

Gabbert et als Post Event Discussion Procedure

Studied in pairs. Each participant watches a video of the same crime from different angles. Both participants discussed what they had seen before completing a test of recall

Gabbert et al Post- Event Discussion Findings

71% of participants mistakenly recalled aspects of the video that were not shown in the video

Strengths of Accuracy of Eyewitness Testimony Misleading Information

- Braun et al: Used misleading advertising material for Disneyland containing information about Bugs Bunny (not Disney). Partciapnts incorprated it into their memory and recalled meeting Bugs Bunny

-Real World Applications: recent DNA have shown mistaken EWT identification was largest factor for convicting innocents and now knows how to stop it

Limitations of Accuracy of EWT misleading information

-Lacks Mundane Realism- Was a lab experiment so it lacked ecological validity- doesn’t represent true crimes/ accident

Loftus and Palmer Procedure

Participants asked to return one week later and asked another questionnaire with leading question ‘Did you see any broken glass

Loftus and Palmer Findinfs

smashed: 16 yes, 34 no

hit: 7 yes, 47 no

control: 6 yes, 44 no

There was no broken glass in the video

Johnson and Scott Negative Effect Procedure

Participants sat in a waiting room believing they were taking part in a lab study

Low anxiety condition: Participants heard a casual conversation and then saw a man walk through the waiting room with a pen and grease on his hand

High anxiety condition: Participants heard a heated argument ending with glas smashing and then saw a man walk through holding a bloody knife

Participants were then shown 50 pictures and had to select the man they saw

Johnson and Scott Negative Effect Findings

Low: 49% could identify

High:33% could identify

What is Weapon focus theory

Focus on the weapon not the face

Yuille and Cutehall Postive Effect Procedure

In an actual crime a gun shop owner shot a their dead. There were 21 witnesses. Participants were interviewed 4-5 months after the incident. The information was compared to the police interviews at the time of the shooting. Witnesses rated how stressed the felt

Yuille and Cutshall Positive Effect Findings

Witnesses were very accurate in what they recalled and there was little change after 5 months. Participants who recorded highest levels of stress were most accurate

Strengths of Accuracy of EWT anxiety

-Valentine and Mesout used heart rate to divide visitors to the london dungeons labrynth into high and low anxiety groups. High were les accurate than low in identifying target person (SUPPORT FOR NEGATIVE)

-Christianson and Hūbinette interviewed witnesses to a bank robbery. Some direct visitors and some bystanders. They found 75% accurate recall across all witnesses , direct victims more accurate suggest anxiety may enhance recall ( SUPPORT FOR POSITIVE)

Limitations of Accuracy of EWT anxiety

-Anxiety may not be relevant to weapon focus: may have focused on weapons because suprised not scared- Pickel (1998) found accuracy in identifying ‘criminal’ was poorest when object was unusual e.g raw chicken or gun in hairdressers