Memory

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Explanations for forgetting:

Memory: The process in which we retain information about past

events.

Interference theory

An explanation for forgetting in terms of one

memory disrupting the ability to recall another. More likely when 2 memories

are similar.

Retroactive interference (retro=backward) occurs

when you forget a previously learnt task due to the learning of a new task.

Later learning interferes with earlier learning - where new memories disrupt

old memories.

Proactive interference (pro=forward) occurs when

you can’t learn a new task because an old task that had been learnt. When what

we already know interferes with what we are currently learning – where old

memories disrupt new memories.

- Evaluation: It’s

artificial. Lab experiments e.g. in the Postman study it required groups to

remember a list of paired words e.g. cat – tree. But, in everyday life the

information we need to recall is different, e.g. people’s faces, their

birthdays, the ingredients of a pizza. So artificial lab studies lack mundane

realism and are low in ecological validity. Therefore, it means we can’t

generalise the findings from such studies to everyday life as there may well be

other factors that influence forgetting.

+ Evaluation: Real

world application. Is interference a better explanation for forgetting than the

passage of time. They asked rugby players to try to remember the names of the

teams they had played so far in that season, week by week. Most players had

missed games, for some the ‘last team’ they played might have been 2+ weeks

ago. The results showed that accurate recall didn’t depend on how long ago the

matches took place. It was also found that the number of games they played in

the meantime was also influential. So if a player’s recall of a team from 3 weeks

ago was better if they had played no matches since then. Therefore, this study

shows that interference explanations can apply to at least some everyday

situations.

Underwood and

Postman:

Aim: To investigate how retroactive interference

affects learning. So to investigate whether info you have recently received

interferes with the ability to recall something you learned earlier.

Method: lab experiment

Procedure: Pts were split into 2 groups. Both

groups had to remember a list of paired words e.g. cat-tree, jelly-moss,

book-tractor. The experimental group also had to learn another list of words

where the second paired word if different – e.g. cat–glass, jelly-time,

book–revolver. The control group were not given the 2nd list. All pts were

asked to recall the words on the first list.

Results: The recall of the control group was

more accurate than that of the experimental group.

Conclusion: This suggests that learning items in

the second list interfered with pts’ ability to recall the list. This is an

example of retroactive interference

Retrieval failure

Retrieval failure = A form of forgetting. It

occurs when we don’t have the necessary cues to access memory. The memory is

available but not accessible unless a suitable cue is provided.

Cue = A ‘trigger’ of information that allows

access to a memory.

+ Evaluation:

Research shows forgetting is due to the absence of cues. Pts were given 5 lists

of 24 words, each list organised into 6 categories. E.g. hut, cottage, tent,

hotel, cliff, river, hill, volcano. Categories weren’t explicit, it was

presumed that they would be obvious to pts. Recall 70% for the first list but

this fell as pts were given each additional list to learn, presumably due to

interference. However, at the end they were given a cued recall test – they

were told the names of the categories as a clue. Recall rose again to about

70%. Therefore, this shows info is available but can’t be retrieved this shows

retrieval failure is a more important explanation of forgetting than

interference.

- Evaluation: The danger

of circulatory, Claims: relationship between encoding cues and later retrieval

is a correlation not a cause. Cues don’t cause retrieval they’re just

associated with it. others argue the encoding specificity principle (ESP) is

impossible to test because its circular. Stimulus leads to retrieval of a

memory then it must have been encoded in memory. If it doesn’t lead to retrieval,

then according to the ESP it’s not been encoded. But it’s impossible to test an

item if it hasn’t been encoded so it can’t be proved.

Type of cue:

Encoding: Memory is most effective if info that

was present at encoding is also available at the time of retrieval. Also states

cue don’t have to be exactly but the closer the cue is to the original item,

the more useful it will be.

Tulving and Pearlstine- Pts had to learn 48

words in 12 categories. There were 2 recall conditions. Either 1. recalling as many

words as they could or 2. they were given cues (category name). Results: 1. 40%

recall, 2. 60% recall. Cues allow us to access memories.

Godden and Baddeley- Investigated contextual

cues. Scuba divers were pts they were tested on land or in water. 4

experimental conditions. Results showed recall was higher when in the same

condition e.g. learning on land and recall on land.

Goodwin et al- Asked male pts to remember words

drunk or sober (3 times the limit in the UK) they were asked to recall the

words after 24 hours. Results showed info learnt when drunk is more available

when in the same state later.

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Types of long term memory

Procedural memory: memory of how to do things

e.g. riding a bike or learning how to read. Such memories are automatic as a

result of repeated practise.

Episodic memory: Personal memories of events,

e.g. what you did yesterday or a teacher you liked. This kind of memory

includes contextual details plus emotional one.

Semantic memory: Shared memories for facts and

knowledge. These memories may be concrete, e.g. knowing that ice is made of

water, or abstract such as mathematical knowledge.

+ Evaluation: real

life applications. Being able to identify different aspects of LTM allows

psychologists to target certain kinds of memory in order to better people’s

lives. evidence shows that episodic memories could be improved in older people

who had a mild cognitive impairment. The trained pts performed better on a test

of episodic memory after training than a control group. Episodic memory is the

type of memory most often affected by mild cognitive impairment, which

highlights the benefit of being able to distinguish between types of LTM.

+ Evaluation: There’s

clinical evidence from people with brain-damage. Several cases of patients who

have suffered brain damage to their hippocampus & have memory deficits:

Clive Wearing and HM Their memory loss tends to be selective. Episodic memory

in both of these men was severely impaired as a consequence of amnesia. They

had difficulty recalling events that had happened from their pasts. But, their

semantic memories were relatively unaffected. E.g. they still knew the meaning

of words. So HM wouldn't be able to recall stroking a dog half an hour earlier

and couldn't remember owning one in the past, but he would never need the

concept of ‘dog’ explained to him over and over again. Their procedural

memories were also intact. They both knew how to tie their shoelaces, how to

walk and speak. In Clive Wearing’s case (he was a professional musician), how

to read music, sing and play piano.

+ Evaluation:

Neuroimaging Evidence. There's evidence from brain scan studies that different types

of memory are stored in different parts of the brain. Pts were asked to perform

various tasks while their brains were scanned using a PET scanner. E - They

found that episodic and semantic were both recalled from an area of the brain-

the prefrontal cortex. This area is divided into 2 areas, one on each side of

the brain. The left prefrontal cortex was involved in recalling semantic

memories. Episodic memories were recalled from the right prefrontal cortex.

Procedural memories, however, were recalled from the cerebellum and the basal

ganglia.

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Multi Store Memory (MSM) Atkinson and Shiffrin

Duration: How long a piece of information can

stay in your memory before it is no longer available.

Haptically: By touch. - Acoustically: By sound.

- Semantically: By meaning. - Visually: By sight.

Capacity: A measure of how much information can

be stored in the memory.

Coding (Encoding): The way that info is changed

so that it can be stored in a memory store. Environmental stimuli enter the

brain and then is stored in various forms.

Forgetting: Memory traces in STM are fragile and

can be lost within 30 seconds, through displacement or decay, unless they are

repeated (rehearsed). Memory in the LTM is lost through decay, retrieval

failure or interference.

Attention: Information is transferred from one

store to another. You pay attention to pass information from the sensory store

to the STM.

Retrieval: The process of getting info from the

LTM involves the information passing it back through the STM so it’s available

for use.

Maintenance rehearsal: Repetition keeps info in

the STM but eventually will create a LTM. Atkinson and Sheffrin proposed a

direct link between rehearsal in STM and the strength of the LTM.

- Evaluation: The MSM

oversimplifies the memory structures and processes. The MSM suggests that the

STM and the LTM are 2 different unitary stores which operate in a single,

uniform fashion. But research opposes this. Someone known as 'KF' suffered from

brain damage which resulted in them having difficulty processing verbal

information in their STM. However, KF's ability to process visual information

was completely normal. This suggests that the STM is a non-unitary store with

different parts dedicated to processing different types of information (haptic,

visual, auditory).

+ Evaluation: Lab

studies on capacity, duration and coding support the existence of separate

stores. Studies using brain scanning techniques have also demonstrated a

difference between STM and LTM, the prefrontal cortex is active in STM tasks

but not LTM ones and found the hippocampus is active in LTM tasks.

+ Evaluation: pts

were given a list of 50 words that they needed to memorize in a given amount of

time. This experiment found that there was a 'recency effect' where the pts

remembered the most recent words that they had read because they had not yet

been displaced from their STM, they also found that there was a 'primary

effect' where the pts remembered the first words on the list because they had

been rehearsed more and thus transferred into their LTM. These findings support

the MSM because it shows that there are differences between the STM and the LTM

and that they are 2 separate, unitary memory stores.

3 unitary stores: sensory memory, short term memory (STM)

and long term memory (LTM).

Sensory Memory: First is the SM its constantly

receiving information, either visually, auditorily or haptically. But most of

this information actually receives no attention and stays in the sensory memory

until it decays (taking a matter of milliseconds). If a person is focusing on a

piece of information, then instead of decaying it will be directly transferred

to the STM.

Short Term Memory: When in the STM, information

is very 'fragile' and likely to be displaced if it’s not rehearsed. The average

duration for a piece of information in the STM is around 20 seconds and the

amount of information that can be held is 7+/-2 items. If the information is

rehearsed and payed attention too, then the information will be transferred to

the LTM.

Long term memory: has a potentially unlimited

capacity and the duration of which a piece of information can be held in the

LTM is unlimited also.

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Cognitive interview

Geiselman et al:

1. Context reinstatement (CR): Recall image of

the scene, the weather, what you were feeling.

2. Report everything (RE): Report every detail

you can even if they seem irrelevant or trivial.

3. Recall in reverse or a different order (RO):

Describe the event from memorable point.

4. Recall from a changed perspective: Describe

the event as it would have been seen from different viewpoints.

Additional techniques:

Minimising distractions.

Asking the witness to speak slowly.

Adapting the language used.

Reducing

anxiety.

Avoiding judgemental/personal comments.

- Evaluation: quantity vs quality: Its meant to

enhance quantity without compromising the quality. Research shows an 81%

increase of correct info but a 61% increase of incorrect info when enhanced CI

was compared to the standard interview. Meaning police need to treat all info

collected from CIs with caution. It doesn’t guarantee accuracy.

+ Evaluation: effectiveness of the CI: A

meta-analysis of 53 studies found an increase of 34% in correct info given in

the CI compared to the standard police interview. The effectiveness may be due

to some individual elements rather than the whole thing. children were

interviewed using 1 technique from the CI the control group were told to 'try

again' recall across the 4 components was similar and no different from the

control group. Pts interviews using report everything and mental reinstatement

caused higher recall.

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Working Memory Model (WMM)

Originally designed by Baddeley and Hitch, the

WMM is an alternative to the multi-store model of memory (MSM), which they saw

as underestimating the complexities of the STM.

How short-term memory works: It has several

different components Each component has a particular function – includes

storage and manipulation and analysis of information It is an active system

which allows us to work things through. 2 tasks can be carried out

simultaneously in STM if they are being dealt with by different parts of the

memory system.

Central executive: Key component Supervises and

coordinates information to and from the slave systems Very limited capacity It

decides what needs to be done and when.

Episodic buffer: Added in 2000 as the model

needed a more general store. Slave systems deal with specific types of

information. Central executive has no storage capacity Episodic Buffer is extra

storage system but with limited capacity. it records events that happen, and

sends information to the LTM.

Visuo- spatial sketchpad- Inner Scribe Active

rehearsal system Processes spatial and movement information. Visual cache

Passive visual store Stores info about visual form and colour.

Phonological loop- Articulatory Loop Active

rehearsal system where words are maintained by sub vocal repetition. Repeats

info from phonological store Inner voice. Phonological store Passive storage

system Holds spoken information Inner ear.

+ Evaluation:

evidence from brain damaged patients: studies on a man called KF whose short

term forgetting of auditory information was much greater than that of visual

stimuli. In addition, his auditory problems were limited to verbal material

such as letters and digits but not meaningful sounds e.g. a phone ringing. his

brain damage seemed to be restricted to his phonological loop.

- Evaluation: evidence

from brain damaged patients: Key evidence for the WMM comes from case studies

of individuals who have suffered from serious brain damage. The process of

brain injury is traumatic, which may change the behaviour of a person making

them perform worse on certain tasks. these individuals have difficulty paying

attention and therefore underperform in some tasks.

Short term and long term memory:

- Evaluation: Duration:

Forgetting things could be due to displacement rather than decay.

+ Evaluation-

capacity: The size of the chunk matters: Research showed that people had a

shorter memory span for larger chunks, e.g. 8 word phrases, than similar chunks

e.g. one syllable words.

- Evaluation: Coding:

LTM might not have been tested. STM was tested by asking pts to recall a word

list immediately after hearing it. LTM was tested by waiting 20 mins, it’s

questionable if that’s testing LTM.

- Evaluation: Duration:

Testing STM is artificial: memorising syllables doesn’t reflect everyday life

where we are trying to remember is meaningful. Although it does have some

relevance when compared to remembering phone numbers or post codes.

- Evaluation: The STM isn’t

the same for everyone: research shows capacity increases with age. 8 year olds

could remember 6.6 digits, 19 year olds could remember 8.6 digits. Could be due

to gradual increase in brain capacity people may have developed strategies as

they got older to remember info by chunking etc.

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Eyewitness testimony

Eyewitness testimony:

Eyewitness testimony: The evidence provided in

court by a person who witnessed a crime, with a view to identifying the perpetrator

of the crime.

Post event discussion: Repeat interviewing: Each

time the witness is interviewed comments from the interviewer could become

incorporated into the recollection of events. Interviewer could use leading

questions to alter the individual’s memory especially when interviewing

children.

Post event discussion: Conformity effect:

Co-witnesses may reach a consensus view of what actually happened. Pts were in

pairs each partner watched a different video of the same event so they viewed

unique items. 71% who had discussed the event went in to mistakenly recall

items acquired during the discussion.

- Evaluation: Individual

differences: Age differences, an eyewitness typically acquires info from 2

sources observing the event and from subsequent suggestions. Compared to younger

people elderly people have trouble remembering the source of the info. They

become more prone to the effect of misleading info when giving testimony.

+ Evaluation: Real

world applications: Criminal justice system relies on eyewitness identification

for investigating and prosecuting crimes. Mistaken eyewitness identification

was the largest factor contributing to the conviction of innocent people.

Accuracy of eyewitness testimony: anxiety

Yerkes Dodson effect.

Evaluation: real life vs lab studies: It was a

study of anxiety in context of a real life crime. lab studies may not create

real anxiety that would be created in an actual crime.

+ Evaluation: Anxiety

can improve accuracy: research shows evidence of enhanced recall when they

questioned 58 real witnesses to bank robberies in Sweden. They were either

victims of bystanders high and low anxiety levels would be shown. Interviews

took place 4-15 weeks after. All showed good memories for details of the

robbery itself (75% accurate recall) witnesses who were more anxious has the

best recall (the victims) so anxiety doesn’t reduce accuracy of recall.

- Evaluation: surprise

not anxiety: pts watch a thief enter a

hairdressing salon carrying scissors (high threat, low surprise) a handgun

(high threat, High surprise), a wallet (low threat, low surprise) or a whole

raw chicken (low threat, high surprise). Identification was least accurate in

the high surprise conditions rather than high threat. weapon focus affect is

based on surprise.

Johnson and Scott

Anxiety reduces the accuracy of recall. The view

of a weapon in a criminal’s hand distracts attention (as anxiety is created)

form other features which reduces the accuracy of identification.

Procedure: Pts sat in a waiting room where they

heard an argument in an adjoining room and then saw a man run through the room

either carrying a pen covered in grease or a knife covered in blood. People

were later asked to identify the man.

Findings: 49% in identifying the man in the pen

condition compared to 33% accuracy in the knife condition. Lotus et al showed

anxiety focuses attention on central features of the crime. Researchers

monitors the pt's eye movement and found that the presence of a weapon caused

attention to be drawn to the weapon and away from the persons face.

Loftus and Palmer leading

questions:

Aim – To investigate whether leading questions

affects the accuracy of EWT after an event.

Experiment 1: Procedure – 45 Pts were shown 7

films of different car accidents. After each film the pts were given a

questionnaire asking them to describe the accident then answer a series of

specific questions about it. One crucial question concerned the speed of the

car on impact. Group 1 got asked ‘How fast were the cars going when they hit

each other?’ Other groups were asked the same question but the verb was changed

to either ‘smashed’ ‘bumped’, ‘collided’, or ‘contacted’. This critical

question was a leading question as it suggested the answer that a pt would

give, therefore encouraging them to provide a certain response.

Results - The verb used significantly affected

speed estimates- Contacted=31.8MPH, hit=34.0MPH, bumped=38.1MPH,

Collided=39.3MPH, smashed=40.8MPH Therefore smashed’ produced the highest

estimate and ‘contacted’ produced the lowest estimate.

Experiment 2: Procedure – A leading question may

bias a pt’s response or cause info to be altered before is stored. A new set of

pts were divided into 3 groups and shown a film of a car accident lasting 1

minute, and asked questions about speed. The pts were asked to return 1week

later, they were asked a series of 10 questions about the accident, including a

critical question, ‘Did you see any broken glass?’ There wasn’t broken glass in

the film but, those who thought the car was travelling faster might be more

likely to think that there would be broken glass.

Results – Pts who had estimated a higher speed

were more likely to have said they had seen broken glass, as indicated by the

findings in the table.

+ Evaluation: type

of method used (lab) and its practical applications.

- Evaluation: Lacks

ecological validity as participants only watched a video clip of the accident.

As it was artificial, participants may be less motivated to remember the

incident. In real life witnessing a crime is more meaningful and important.

-Evaluation: Demand characteristics

The eye witnesses knew they were taking part in an experiment, may not have

taken the task as seriously as if it was real life. Demand characteristics could have affected

the pts behaviour, they may have worked out the aim of the experiment and

estimated faster speeds in the ‘smashed’ group on purpose. This could make results less valid as they

may not be a realistic measure of the effect of misleading info on EWT, so can’t

generalise findings to real life EWT accounts.