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Multi Store Model Of Memory

Sensory register: Stimulus from environment pass into register

One for all senses

Two Main:

Iconic memory : Visually coded

Echoic Memory: Coded acoustically

Duration: less than half a second

High capacity

Only some info gets passed -Pay attention

Short term memory:

Limited Capacity: 5-9

Coded Acoustically

Duration: 18-30 seconds

Maintenance rehearsal- Repeating material to self- Keeps Info in STM

Long Term Memory:

Permanent store- For info rehearsed

Capacity: Unlimited Link to Bahrick et al PP able to recognise school mates

Coding: Semantically

To recall info: Transferred to STM (Retrieval)

Evaluation:

Evaluation: Supporting evidence

Shows STM and LTM are different

Baddeley: Mix up words sound similar with STM, Mix up similar meaning using LTM.

This study shows how stores are coded.

So supports MSM view that stores are separate and independent.

Extra Evaluation: Baddeley study used artificial stimuli.

More type of STM: Shallice and Warrington studied patient with amnesia known as KF

KF had a digit span of only one or two items

Have more difficulty recalling verbal items (numbers and digits

read out loud) than visual items (pictures).

STM for digits poor when read out loud to him

Recall was much better when able to read digit to himself

KF’s short-term forgetting of auditory letters and digits (things that are heard) was much greater than his forgetting of visual stimuli.

Showed could be store for non verbal sounds

Unitary STM is a limitation - Research shows must be a STM to process visual info and another to process auditory.

More than one type of rehearsal

Craik and Watkins- what matters about rehearsal is the type

Two types of rehearsal. Maintenance R does not transfer info to LTM. Just maintains info in STM

Elaborative Rehearsal needed for long term storage.

Occurs: Think about meaning of info or link to existing knowledge

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TYPES OF LONG TERM MEMORY

Episodic memory: Ability to recall events

Examples: Recent visit to dentist, Lecture you went to yesterday

Time stamped- When they happened

Several elements: people, places, objects, behaviours

Conscious effort to recall episodic- Search for memory

Semantic Memory: Knowledge of the world.

Knowledge of things like: Applying to university, taste of orange, meanings of words.

Contains knowledge of celebrities, animals and love

Not time stamped

Procedural Memory:

Memory for actions, skills, how we do things

Without conscious awareness or great effort

Example: Driving a car-change gear without realisation

Evaluation:

Clinical evidence: HM and Clive Wearing

Episodic memory in both men impaired as consequence of amnesia

Difficulty recalling events

Sematic memory unaffected-understood meanings of words

Procedural memory intact- Could walk, speak, play piano, read

Supports diff types of LTM.

One store damaged others unaffected

Evidence that types of memory are diff and stored in diff part of brain

Research methods that were used on HM mainly included interviews with the patient and people who they regularly interacted with, as well as observation of the patient

Research methods that were used on Clive Wearing were mainly interviews with the patient as well as interviews with the patient’s wife. This allowed in-depth information to be revealed by both the patient himself as well as noticeable differences by people that are around him

Deborah, Wearing’s wife, who was the source for many of the interviews in order to obtain information, is extremely subjective and opinionated and thus may not be as factual as possibleAs with HM, Wearing cannot remember his consent, or remember the aim of the experiment and investigation the whole way through, and thus when he is participating in the experiment, he is not continuously aware of the aim and what he is doing. In this, there are ethical concerns that Wearing cannot stop the experiment, nor is he fully aware of what is going on

Lack of control of variables

Neuroimaging evidence:

Brain Scans- Diff type of memory stored in diff part of brain

Tulving: Got PP to perform task whilst using PET scanner.

Found: Episodic and semantic both recalled from area of brain= prefrontal cortex .

Left PC recalled semantic memories

Right Pc recalled Episodic memory

Strength: Gives physical evidence to diff types of LTM.

Supported by other studies ---- Increase Validity

Real life application: Allows psychologist to target certain kinds of memory to better people's life

Belleville et al: Demonstrated episodic memories could be improved in older people with mild cognitive treatment .

Trained PP's performed better on test of episodic memory after training than a control group.

Episodic memory- Most affected by mild cognitive impairment. So enables specific treatment.

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The Working Memory Model

Explanations of how the STM is organised and how it functions.

Concerned with the part of the mind that is active when we are storing and manipulating info

Central executive: attentional Process that monitors incoming dat. makes decisions and allocates slave systems to task.

Very limited Capacity

Phonological loop: It deals with auditory information

Sub division

Phonological store: Stores the words you hear.

Articulatory process: Allows maintained rehearsal

Visuo=spatial sketchpad

Stores visual or spatial info.

For example, Remembering amount of windows in house, you visualise it

Limited Capacity--- Baddeley says its abt 3-4 objects

Logie divided VSS into

Visual Cache, stores visual data

Inner scribe: Records arrangement of objects in the visual field

Episodic Buffer:

Temporary store for info

Added later to account for both visual and acoustic info

Records events that are happening

Storage component of CE

Limited capacity of 4 chunks

Links working memory to LTM

Evaluation:

Clinical evidence: KF suffered Brain damage and had poor STM ability for verbal info but could process visual info presented visually.

For example: Difficulty with sounds but could recall letters and digits

Suggest: Jus PL had been damaged leaving other areas of memory intact

Supports: There is a separate visual and acoustic store

Not reliable because unique case concerned with traumatic experience

Cant be generalised

Dual task performance: Support existence of VSS.

Baddeley showed that PP's had more difficulty doing two visual tasks than doing both a visual and verbal task at the same time.

Increased difficulty is because both visual task compete for same slave system whereas doing a verbal and visual at the same time there is no competition.

This means that there must be a separate slave system (The VSS) that processes visual input.

Lack of clarity over the CE: Doesn't explain anything

'The CE is the most important but the least understood component of working memory'

Needs to be more than just attention

WMM hasn't been fully explained.

The major weakness of the working memory model is the central executive which, ironically, is its most important component. There is relatively little research evidence for its existence and it is by its nature very hard to directly investigate, although some recent research into patients with Alzheimer’s disease (e.g. Baddeley et al, 1991) has identified how an impaired central executive may affect memory function. The problem with researching the central executive is that it cannot itself be measured directly, and instead its function has to be inferred from performance at verbal and visual tasks. When we want to measure the functioning of a component we give it a task designed to reduce its performance, such as occupying the phonological loop with an articulatory suppression task. If participants are able to perform the task then researchers conclude that the central executive is working properly, but if they perform the task poorly then they conclude that the phonological loop is impaired. In other words it is impossible to design a task that effectively tests the central executive without also affecting its slave systems, and so the central executive may never be adequately investigated and it will always remain a concept with limited support - Richardson (1984) calls this the circular argument.

The existence of the phonological loop was demonstrated by Baddeley et al (1975) with their study of the word length effect. If there is a phonological loop that lasts for about 20-30 seconds then it would make sense that it could store more single syllable words (short words) than it could multi-syllabic words (long words) as it takes longer to say multiple syllables than it does a single syllable. Badeley et al found that participants could indeed remember more single syllable words than multi-syllablic ones, and they called this the word length effect. However when they were prevented from rehearsing the words (by giving them an interference task that creates articulatory suppression, such as counting backwards in threes) the word length effect disappeared as they were unable to use their phonological loops for remembering the words because it was engaged in the articulatory suppression task. This provides strong evidence that the phonological loop exists.

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EXPLAATIONS FOR INTERERNCE

Interferences: when two pieces of info conflict with ach other resulting in forgetting or one or both memories to be distorted.

Main reason for forgetting in LTM

Types of Interference

Proactive: Older memory interferes with a newer one.

For example: Teacher learned so many names in the past she has difficulty remembering names of current class

Retroactive: Newer memory interferes with an older one

For example: Your teacher has learned so many names this year she has difficulty remembering the names of the student last year

Effects of Similarity

McGeoch and William McDonald studied retroactive interference

Aim: To investigate whether interference is worse when memories are similar

Method: Changing the amount of similarity between two sets of materials

PP's had to learn a list of words until they could remember them with 100% accuracy

They then learned a new list.

There were six groups of PP's who had to learn diff types of list

G1: Symons

G2: Antonyms

G3: Words unraked to original ones

G4: Nonsense syllables

G5: Three digit numbers

G6: No new list

Findings: Most similar material produced worst recall .

Shows interference strongest when memories are similar.

Evaluation

Evidence form lab studies: Lab experiments carried out into explanation for forgetting

Such as McGeoch and McDonald's research

Shows both types of interference ate common ways we forgot info from LTM

Strength: Lab experiments control the effects of irrelevant influences and gives us that interference is a valid explanation for forgetting

Time between learning:

Lab experiments designed so that the possibility of interface is maximised.

One example of how this occurs is in the time periods between learning list of words and recalling them.

For example, a PP might have to learn two list in 20mins. Researchers reduce the whole learning experience into a short time.

This does not reflect how we learn in real life.

So conclusion cant be generalised outside the lab as role of interference might be exaggerated.

Artificial Methods: Stimulus materials are list of words

Different from things we learn and try to Remember in everyday life like peoples faces, birthdays and ingredients for cooking.

Limitation: May not be as likely an explanation for forgetting in everyday life as it is the lab

Real life studies: Baddeley and Hitch wanted to find out if interference was a better explanation for forgetting than the passage of time.

Asked Rugby pales to try and remember the names of the teams they had played so far in that season, week by week.

Some players missed matches for last game might have been weeks ago

Result: Accurate recall did not depend on how long ago the matches took place.

Much more important was the number of games played in the meantime.

Players recall of a team they had played no matches since then

Shows inference applies to everyday situations

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Retrieval Failure

People may forget because there are Insufficient cues.

When info is initially y placed in memory, associated cues stored at the same time.

If cues are not available at time of recall, it appears as if you have forgotten the info but this is due to Retrieval failure

Retrieval failure: Form of forgetting that occurs when cues are present to access memories. Memory available but not accessible unless a suitable cue is provide

Encoding Specificity Principle

Sates that if a cue is to help us recall info it has to be present at encoding (when we learn info) and present at retrieval when we are recalling it.

If cues available at encoding and retrieval are different or absent at retrieval then there will be some forgetting

Cues are linked to material to be remembered in meaningful way.

For example 'STM' LEADS TO RECALLING INFO ABOUT STORT TERM MEMORY

Some cues not in a meaningful way

Context Dependent Forgetting

Godden and Baddeley.

Procedure: Divers learned list of words either underwater or on land and then were asked to recall words either underwater or on land.

4 conditions created:

Learn and recall on land

Learn on land and recall underwater.

Learn underwater and recall underwater

Learn Underwater and recall on land

Findings: Accurate recall was 40% lower in non matching conditions. the external cues available at learning were different from ones at recall and this lead to retrieval failure

State Dependent Forgetting

Carter and Cassaday

Procedure: Gave anti-histamine drugs to PP's. Drugs had a mild sedative effect making PP's drowsy.

this creates an internal physiological state differs from normal state of being awake and alert

PP's had to learn list of words and then recall info

4 conditions:

Learn on drug and recall when on it

Learn on it and recall when not on it

Learn not on drug and recall when on it

Learn not on it and recall when not on it

Findings: Conditions were there was a mismatch between internal state at learning and recall, performance on memory was worse

When cues absent more forgetting

Example: You are drowsy when recalling info but had been alert learning it

Evaluation

Supporting evidence: One prominent memory researcher, Michael Eysenck argues retrieval failure is perhaps the main reason for forgetting from LTM

Strength: Supporting evidence increases the validity of an explanation.

True if it happens both in real life situations and highly controlled conditions of labs.

Questioning context effects: Baddeley argues that context effects are actually not very strong especially in real life.

Different Contexts have to be very different before an effect of forgetting is seen

For example, it will be difficult to find an environment as different from land as underwater.

Whereas in real life, someone may learn something in one room and recall it another.

However, this is unlikely to lead to forgetting because these environments are generally not different enough

Limitations: Real life applications of RF due to contextual cues don't actually explain much forgetting.

Recall versus recognition

Godden and Baddeley used recognition test instead of recall in a replication of underwater experiment

PP's said hey had to say whether they recognised a word read to them from the list instead of retrieving it them self.

When recognition was tested, there was no context dependent effect; performance was the same in all four conditions.

Limitations: Means that the presence or absence of cues only effects memory in a certain way.

Problems with the ESP

The ESP cannot be tested.

It leads to circular reasoning.

In experiments where a cue produces the successful recall of a word, we assume that the cue must have been encoded at the time of learning.

If a cue does not result in a successful recall of word then it is assumed that thee cue was not encoded at the time of learning.

These are just assumptions-There is no way to establish whether or not cue has been encoded

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Misleading Information

Procedure: Loftus and Palmer

PP's watched film clips of accidents and then gave them questions about the accident

In the leading question PP's were asked to describe how fast the cars were travelling

For example, How fast were the cars going when they hit each other?

5 groups each with different verbs like contacted, bumped, collided, smashed.

Leading question as verb suggest speed car was going

Findings: Verb contacted in a mean estimated speed of 31.8 mph

Why do leading question affect EWT

The response bias explanation suggests that the wording of the question has no affect on PP's memories but influences how they decide to answer.

For example if the word smashed is used, encourages them to choose a higher speed

Substitution explanation---The wording of a leading questions actually changes the PP' memory of the film clip. This was demonstrated because PP heard the word smashed were more likely to report seeing broken glass than those who heard hit. Verb altered memory of incident

Post event discussion

Gabbert et al studied PP's in pairs

Procedure:

Each PP watched a video of the same crime but filmed from different points of view.

This meant PP could see elements of events other could not see

Both PP then discussed what they has seen individually completing a test of recall.

Findings:

71% of PP mistakenly recalled aspects of the events they did not see in the video but had picked up in the discussion.

The figure in the control group where there was no control group was )%

Conclusion: Witnesses often go along with each other to win social approval or they believe the other witnesses are right and they're wrong.

Phenomenon memory conformity

Evaluation

Useful real life applications:

Strength:

Practical use in real world, where the consequences of inaccurate EWT can be very serious

Loftus believes IQ can distort memory

This means that police officers can make important positive difference to the lives of real people.

By improving the way legal system works.

Tasks are artificial: PP watched film clips of car accidents.

Different experience form witnessing a real accident.

Lacks stress of real accident

Emotions can influence memory

Limitation: Tells us little about how LQ may affect EWT in cases of real accident or crimes.

Individual differences: Older people less accurate tan younger people when giving EWR

For example, Anastasi and Rhodes found age groups 18-25 and 35-45 were more accurate than people 55-78

All age groups more accurate when identifying people of their own age group (own age bias)

Demand Characteristics: Zaragoza and McCloskey argue answers PP give in lab studies of EWT are as a result of DC.

PP's don't want to let the researcher down and want to appear helpful.

So when they are asked a question they don't know the answer to, they guess especially if its a yes or no question.

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Anxiety

Anxiety has a negative recall: Anxiety creates physiological arousal which prevents us paying attention to important cues.

Effects of weapons:

Johnson and Scott

Procedure: led PP's to believe they were taking part in lab studies

Whilst in a waiting room PP's heard an a argument in the next room.

Low Anxiety Condition: Man walked through waiting area carrying pen and with grease on his hands.

High Anxiety Condition: Other PP's heard same heated argument but with a sound of breaking glass.

A man walked out of the room, holding, paper knife covered in blood.

Findings: PP's picked out man out of set of 50 photos

49% who saw man holding a pen able to identify him

Holding a knife was 33%

Tunnel theory of memory argues that witness's attention narrows focus's on weapon because its a source of anxiety

Anxiety has a postive effect on recall

Anxiety triggers fight or flight response which increases alertness and improves memory for event as we become more aware of cues.

Yuille and Cutshall

Procedure: Conducted study of real life shooting in a gun shop in Vancouver, Canada.

Shop owner shot a thief dead

21 Witnesses and 13 agreed to take part in study

Interviews took place 4-5 months after the event.

The eyewitness accounts provided in both the police and research interviews were analysed and compared.

Accuracy was determined by number of details in each account.

The witnesses were also asked to rate how stressed they had felt at the time of the incident, using a 7 point scale.

Asked if any emotional problems after event

Findings: Witness accurate in accounts

Little change in the amount of accuracy after 5 months

Those PP's reported with highest levels of stress were more accurate.

88% compared to 75%

Explaining The Contradictory Finidngs

Yerkes and Dodson: Relationship between emotional arousal and performance looks like and inverted U

Deffenbacher took Y-D Law and applied it to EWT.

Lower levels of anxiety produce lower level of recall accuracy.

Memory becomes more accurate as the level of anxiety experienced increases.

Comes to a point where optimal level of anxiety is reached.

If witness experiences more stress than this, recall declines.

Evaluation:

Weapon focus effect may not be relevant:

Johnson and Scott's study on weapon focus may test surprise rather than anxiety

PP's focus on weapon because they are surprised of what they see then because they're scared.

Icicle conducted experiment using scissors, handgun, wallet, raw chicken

Eyewitness accuracy poorer in high unusualness conditions

Weapon focus effect due to unusualness rather than anxiety.

Tells us nothing about the effects of anxiety on EWT