P1 - Memory Flashcards

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1
Q

What does HM case study show us?

A

I tells us that the hippocampus is responsible for consolidation memory

Without the hippocampus he struggled to turn short term memory into long term memory

He was able to train his unconscious memory but not his conscious memory therefore the hippocampus is not responsible for unconscious memories

Re-enforces the idea that short term memory and long term memory are different things but also long term memory has different parts; procedural and epistemic memory

Case study is when you are learning a lot of information about a single person

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2
Q

three assumptions of the Multi store model

A

memory is made up of discrete memory stores. Each store can be differentiated based on capacity, duration and the way it is coded. Coded is looked at badly

Attention and rehearsal are essential processes in the transfer of information from the sensory register to LTM, via STM

The transfer of information is linear(sequential,)which means that material must pass through each component before being stored in LTM

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3
Q

draw the msm model

A

see online

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4
Q

name the 3 components of msm model and the characteristics of each one (CAPACITY / DURATION / CODING / FORGETTING) make a a table

A

Sensory Register - large, 1/4 to 1/2 a second, sense specific, decay

Short Term Memory - 7 items (miller), 12-18 seconds, encoding specifically acoustic, Displacement = capacity
Decay = duration

Long Term Memory - unlimited capacity , minutes to lifetime , sematic and virtual , Retrieval failure, interference

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5
Q

evaluate the msm (against) (2)

A

There is research to support that there are three discrete stored in memory (SM, STM, LTM) , which suggests that STM and LTM are independent stores.
For example, research has shown that the capacity of STM is 7+ -2 chunks (Jacobs & Miller), while the capacity of LTM is extremely large Bahrick et al). Furthermore, in STM is encoded acoustically and LTM is encoded semantically (Baddeley).

Neurological evidence can explain how some aspects of memory can remain intact after brain damage to one part of the brain.
This can explain the case with HM whose STM continued to function while LTM didn’t and Squire et al. (1992) has used neuro-imagery to show that, in an anatomical sense, STM & LTM are separate components.

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6
Q

study for the death of the MSM

A

One of the most disputed assumptions is that memory is a linear. According to this assumption, LTM must be activated before some processing in STM. This assumption cannot explain the KF case study, as KF had a normally functioning but a limited (1 digit). Ruchkin et al. (1999) found that LTM is accessed before STM in the memory process. Therefore, memory must be interactive rather than sequential or linear.
(death of the multi store model)

Due to these limitations, the MSM has been superseded by the working model memory which can account for alternative & interactive pathways, neurological evidence and that fact that participants can process two tasks at the same time.
(memory has to be interactive)

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7
Q

name the 3 different sensory registers

A

Iconic memory is the visual sensory memory (SM) register pertaining to the visual domain and a fast-decaying store of visual information.

Echoic memory is one of the sensory memory registers; a component of sensory memory (SM) that is specific to retaining auditory information. The sensory memory for sounds that people have just perceived is the form of echoic memory.

Haptic memory is a part of the sensory register that recalls stimuli acquired by touch

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8
Q

what is the capacity and duration of the iconic register?

And also a research study to support this?

A

Limited capacity (9-10 items) Very short duration (by time takes to report 4 letters whole image has decayed) 

Research Study - Sperling (1960)
Sperling presented participants with a 4 x 3 matrix of letters for 0.05 seconds (50 ms).

recalled low amount but reported to have ‘seen more’
participants are processing the whole of the matrix, which they are able to recall for a very brief period of time before it decays and is forgotten. 

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9
Q

study into the echoic memory?

A

Research Study - Darwin, Turvey & Crowder (1972)

Aim: To investigate the duration and capacity of echoic sensory register.

Method & Procedure:

Participants were presented with spoken recording of lists of number and letters over a set of headphones. The stimuli were made up of 9 numbers between 1-10 (omitting 7) and nine letters BFJLMQRUY, which were randomly assigned to three item stimuli set. When making the stimuli sets the following rules were applied: (1) each item list contained two items of one category and one of the other & (2) each stimulus had four items of one category and five of the other.

Shortly after simultaneous presentation of the three stimuli, the participants were given a cue (a line indicating left, middle or right) to recall one of the stimuli.

Independent variable was the time between presentation and the cue 0, 1, 2 or 4 seconds.

Darwin found that partial reporting of one stimuli was successful, but that participants weren’t able to report the whole of the stimuli set.

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10
Q

study into the haptic memory?

A

Bliss found that haptic memory has a similar duration and capacity as iconic memory (Sperling 1980)

Duration ~ 2 seconds
Capacity – 4-5 items, but participants perform well when partially reporting a stimulus.

Haptic and iconic memory have similar functions.

Research Study – Gilson & Baddeley (1969). 

Gilson & Baddeley (1969) asked participants to perform a localization task, where they had to point to the exact location that they were touched.

The independent variable(s) in the study was the retention interval, in seconds and also whether participants were asked to perform a secondary interference task (counting backwards in threes). 

Dependent Variable - spatial deviation of participants point responses (mm). 

Gilson & Baddeley (1969) estimated that the duration of the haptic register was about 10 seconds, after 10 seconds recall required verbal rehearsal in short term memory. 

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11
Q

practical application of research into the digit span technique (stm)

A

post codes in the uk are chunked eg (b93 3bj)

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12
Q

explain the two different types of interference?

A

proactive = old information will interfere with new information

Retroactive = new information will interfere with the recall of old information

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13
Q

explain coding in the STM and a study that supports it

A

Encoding can be understood as the way in which memories are represented in STM and LTM

Research Study - Conrad (1964)

List 1: B G C T D V

List 2: F J X M S R

Conrad presented participants with a sequence of letters either like list 1 or list 2, which they were asked to recall in order.

Conrad’s findings -

Conrad (1963, 1964) found that sequences of items which are acoustically similar are more difficult to remember, even though presented visually.

This shows that short term memory is (en)coded acoustically (i.e. by sound) rather than visually.

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14
Q

problems with studying the long term memory

A

Long time period

Don’t know how accurate finding are

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15
Q

study into the capacity and duration of the LTM

A

Research Study - Bahrick et al (1975)

Aim
To investigate the duration (and capacity) of Very-Long-Term-Memory

Procedure
An opportunity sample of 392 US ex-High-School students aged between 117 & 74 was used. The time since leaving High school was up to 48 years. There participants were tested in 4 ways:
There is no aid/cue to prompt
1. Free recall of the names of as many of their ex-classmate as possible.
2. A photo recognition test. The participants were asked to identify their former classmates from a set of 50 photographs.
3. A name recognition test
4. A name and photo matching test.

It is likely that they are not forgetting down to decay
It is down to retrieval failure

Face & name recognition - 90% accuracy in the face and name recognition in participants who had left school 34 years previously. This dropped to 80% after 48 years and 40% after 48 years for face recognition.

The capacity is very large if it can remember up to 48 years

Free recall – 60% accuracy after 15 years and 30% after 48 years.

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16
Q

study into the capacity and duration of the LTM

A

Research Study - Bahrick et al (1975)

Aim
To investigate the duration (and capacity) of Very-Long-Term-Memory

Procedure
An opportunity sample of 392 US ex-High-School students aged between 117 & 74 was used. The time since leaving High school was up to 48 years. There participants were tested in 4 ways:
There is no aid/cue to prompt
1. Free recall of the names of as many of their ex-classmate as possible.
2. A photo recognition test. The participants were asked to identify their former classmates from a set of 50 photographs.
3. A name recognition test
4. A name and photo matching test.

It is likely that they are not forgetting down to decay
It is down to retrieval failure

Face & name recognition - 90% accuracy in the face and name recognition in participants who had left school 34 years previously. This dropped to 80% after 48 years and 40% after 48 years for face recognition.

The capacity is very large if it can remember up to 48 years

Free recall – 60% accuracy after 15 years and 30% after 48 years.

Conclusions

Recognition is better than recall & classmates are rarely forgotten once recognition cues have been given.

It is not that the memory is not there (decay), it is retrieval failure. We can use cues
If we are to remember information for 48 years then we know that LTM has a very large capacity

Bahrick et al acknowledged that there were a number of extraneous variables in their study that were difficult to control. Identify possible extraneous variables and explain how they might have influenced the results & conclusions.

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17
Q

evaluation of Bahrick et al research (3)

A

Comment on the internal validity of Bahrick’s research (provide examples)

There was likely a yearbook with the names and faces of most of the people in the task, different students may have looked at the yearbook more than others and therefore had an advantage over students who did not. The participants could have been reading their yearbooks regularly and using rehearsal.
They might still be friends and refreshing the memory through seeing these people would give an unfair advantage
If participants had a closer connection to the students then they may have thought about them more regularly
Lacks internal validity as there is very little control over it

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18
Q

study into how long term memories are coded?

A

Research Study - Baddeley (1966b).

Aim – was to investigate whether LTM was coded acoustically like STM or somatically

Method, design & procedure.

Word sequences (10 words in length) were presented 4 times, after which participants spent 20 minutes on an interference task (involving immediate memory for digits). After 20 minutes, participants recalled the word list in serial order.

Baddeley knows that the capacity is LTM is longer than STM
Must be above 30 seconds to go into LTM

findings - acoustical similar = 85%
semantically similar = 55%

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19
Q

Compare Baddeley’s 1966a findings and his 1966b findings and explain what they show.

A

A suggests that semantically similar is greater than acoustically similar to in terms of percentage.

A findings also suggest that short term memory decayed when the letter sequences were acoustically compared to somatically.

B findings suggests that LTM decayed more when the words were semantically similar.

STM is coded acoustically and LTM is semantically.

This is another example of how we know the STM and LTM are different, this is because they are coded differently.

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20
Q

core study into Working model memory

A

Baddeley & Hitch 1974 (this is the main study)

To test the concept of working memory, Baddeley and Hitch developed a dual task paradigms. This is where participants perform a primary task whilst simultaneously performing a secondary task which is presumed to take up STM capacity.

Procedure.

Participants complete a reasoning task, while rehearsing digits simultaneously.

Primary task: reasoning task.

e. g., A precedes B: AB (TRUE)
e. g., B is not preceded by A: AB (FALSE)

Secondary task: participants are asked to remember (and overtly rehearse) sequences of digits.

Findings

As digit load increased, so did the reasoning time

Conclusion & analysis (can the MSM explain these findings?)

Participants made very few errors when completing the dual task, which cannot be explained by a passive STM (In MSM.)

STM memory must have more than one component for reasoning, understanding and learning.

STM is a workspace where a variety of operations occur.

21
Q

describe the WMM

A

DRAW DIAGRAM - SEE ONENOTE

Lines from each part of the crystalized system allows information to be passed between the two as they all work together

Each part works individually and you can use each at the same time

For example; a taxi driver can speak at the same time as they are driving

We would panic if the driver started using their phone (visual semantics) and driving (visual semantics,) each part has a limited capacity and if you give one too much to do then it cannot handle it.

On the basis of their experiments, Baddeley & Hitch suggested that working memory consists of several components. These components include modality- based stores and a central executive which controls them.

Since the Working Memory Model extends our understanding of STM, it means that the components of the WMM all have limited capacity and duration as we have seen in the characteristics of the STM in the MSM. It also works with acoustic and visual encoding.

22
Q

describe and explain the central executive

A

The central executive is considered the most important part of working memory, because it controls attention and coordinates the actions of the other components. It has a limited capacity. The central executive is modality free, which means that it can store information in any sense modality.

The central executive would be activated when stimuli need to be manipulated. An example of manipulation would be the process of reordering the digits in the telephone number (e.g., in descending numerical order).

23
Q

describe and explain the phenological loop

A

The phonological loop is a limited capacity, temporary storage system for holding verbal information in a speech based form. Temporary storage of a phonological representation of an unfamiliar telephone number would engage the PL.

Monkey game: Children hear a number of spoken words which they have to recall backwards

Mono syllabic = cat, leg, ball
Poly syllabic = basketball, dishwasher

There are two components in the PL, the primary acoustic (phonological) store and the articulatory control process).

  • Articulatory Control System (The Inner Voice) The articulatory control system rehearses information verbally and has a time based capacity of about 2 seconds. It is helpful to think of it as the system that you use to mentally rehearse information by repeating it over and over again.
  • Primary Acoustic (phonological) Store (The Inner Ear) The phonological store uses a sound based code to store information, but this information decays after about 2 seconds, unless it is rehearsed by the articulatory control system. The phonological store receives its input either directly from the ears or from long term memory.
24
Q

describe and explain the visuospatial sketchpad

A

The visuospatial sketchpad stores and manipulates visual information, input is from the eyes or long term memory. Maintenance of an image of its visual appearance would engage the VSSP; if you imagine an object and then picture it rotating you are using your visuospatial sketchpad. Logie suggested the PL was subdivided into:

Inner scribe which is responsible for spatial 3D tasks

Visual cache which is responsible for shape and color identification

25
Q

describe and explain the episodic buffer

A

The episodic buffer is a fairly recent addition to the working memory model (Baddeley, 2000). Its purpose is to provide temporary storage for the components in all modalities.

26
Q

evaluate the WMM (supporting)

A

Research Evidence: The WMM is supported from dual task studies and physiological evidence from brain scans…

Baddesley and Hitch - Dual task paradigms suggested that STM must have more than one component for learning

STM has many components

The dual task paradigms results suggested that the participants were able to do two tasks

Suggest the central executive controls them

Cant overload the components, must give the components one task each (visuospatial sketchpad) (phenological loop)

‘Reciting number sketchpad
Alphabet is loop
They were able to do this’

Neurological research - Phenological loop is responsible for verbal tasks in the left hand part of the brain

Visuospatial sketchpad is in right side of brain

Supports the WMM as the components are separate from each other

27
Q

research against the WMM

A

E.g. Musical memory

Bertz found people can listen to music without impairing phonic tasks, which suggests it isn’t fully defined and complete

28
Q

Compare and contrast the WMM and MSM?

A

Despite this criticism it can still be argued that the WMM is better than the MSM due to the fact that it is more effective in explaining short-term memory. The multi-store model suggests that STM consists of just one component whereas the WMM going into much further detail into the different components of the STM (phenological and visuospatial.) This is not effective for explaining the Musical memory research as it suggests that there would be sensory overload when two phonological tasks took place at the same time; but this doesn’t happen.

Refer to Baddeley and Hitch dual task which suggests that the STM is two components

Don’t have to rehearse and it doesn’t rely on this process
Linear – kf shows that the memory is interactive rather than linear and we can manipulate material and move info from the LT to different parts of the brain

29
Q

study to support the central executive?

A

Research Related to the Central Executive (controls the slave system) (evaluation of working model memory)

“In some ways the central executive functions more like an attentional control system than a memory store” Baddeley (1997)

The CE is responsible for.

The central executive has a critical role in attention, planning and coordination. It is so complex that it is much more difficult to work out what it does and what it doesn’t.

Research Study - Baddeley (1996)

Baddeley investigated the action of the CE by asking people to generate random digit strings while reciting the alphabet, counting up from 1, alternating between counting and reciting the alphabet. Baddeley measured how random the lists were.

Findings & Conclusions:

Baddeley found that the digit string became increasingly less random in the final condition when participants were having to switch between reciting the alphabet and reciting numbers. This was because the alphabet and the number cats tasks were competing for the same central executive resources.

30
Q

study relating to the phenological loop

A

The Word Length Effect. Baddeley et al. (1975)

Results: Memory span for mono syllabic words is greater than span for poly syllabic words.

Explain what these results show researchers about the capacity of the phonological loop (is capacity a passage of time or a number of digits / chunks?)

 capacity is a passing of time rather than a number of loops or chunks

Capacity of loop = 2 secs
Memory is more of a tape than a box of chocolates

Evaluation: 1 syllable = 1 chunk

Always use the STM(7+2) chunks and then evaluate with WMM(phenological loop 2 seconds)

31
Q

study for the visuo-spatial-sketchpad

A

Research study - Case Study - KF

Case studies of brain damaged patients may provide some support for th WM model. Shallice and Warrington (1974) studied KF, a man whose brain had been injured in a motorcycle accident. KF’s LTM functioned normally, but his STM was severely impaired. Instead of around 7 items, KF was only able to recall 1 or 2 items from a list. Further investigation showed that KF forgot letters and digits much faster when he received them auditorily than visually. It was also found that KF had a normal STM span for meaningful sounds (e.g. a doorbell, a telephone ringing, a cart mewing) even though his STM span for words, letters and digits was very limited. The uneven pattern of deficits suggests that KF had more than one STM store, which is consistent with the WM model.

It supports the working model memory because he remembered the digits for longer of visual rather than auditory which shows that they are disassociated

32
Q

what does cohen argue in terms of LTM

A

Cohen argues that there aren’t three type of long term memory, but rather two types; declarative and non-declarative memory. Declarative includes both episodic and semantic.

Declarative = conscious memory
Non declarative = unconscious memory

33
Q

Declarative Memory (Episodic and Semantic Memory)

what is episodic memory

A

Episodic memories are sometimes referred to as autobiographical memories. It is in episodic memory that personal experiences are stored (e.g. getting your exam results). The strength of episodic memories is influenced by emotions, degree of coding.

The pre-frontal cortex is associated with initial coding of episodic memories, with consolidation and storage in the neocortex. Memories for the different parts of the event are stored in different areas, but are connected together in the hippocampus.

Moderating variables - gender
Girls are more emotional and think more about an event after it happens rather than a male does

34
Q

what is semantic memory

A

Semantic memory contains all of the general facts about the world (e.g. David Cameron is the prime minister). Semantic memories are more robust than episodic memories, but their strength is still determined by coding

Semantic memories are linked to episodic memories (e.g. I was on holiday in Snowdonia when David Cameron was elected as prime minister in May), but overtime semantic memories are not time stamped. In other words, semantic and episodic memories are divorced from each other.

35
Q

study for semantic and episodic memories

A

CL Case Study – Vicari et al. (2007)

Brain damage after a tumor. CL demonstrated deficiencies in their episodic LTM (esp creating new episodic memories), but was still able to create and recall semantic memories.

36
Q

what is procedural long term memory

A

Procedural LTM is a type of implicit (non-declarative) memory permitting individuals to perform learned tasks with little conscious thought – automatic memory. Procedural memories are difficult to describe, which is why it is often referred to as non-declarative memory.

Procedural memory is important in lots of processes, including language development.

37
Q

study to support procedural memory

A

Research Study – Milner (1962)

Milner (1962) discovered that HM was able to learn to trace a shape using a mirror image, and retain this skill over a number of days. However, he had no conscious (explicit) memory of having done the mirror drawing task before (___________ memory).

38
Q

study to support the role of neurotransmitters

A

Van Gorp et al (1999)
Compared heavy cocaine users with controls, for 45 days after the users abstained from the drug. The cocaine users showed faster increase in procedural memory. It was suggested that the difference in the two conditions was caused by the increase in dopamine production, found when people use and then abstain from using cocaine. Therefore, dopamine might be an important NT when examining the bio-psychology of procedural memory.
Comes down to our biochemistry

39
Q

two explanations for forgetting

A

proactive and retroactive interference and retrieval failure due to absence of cues.

Forgetting in Long Term Memory is often explained by interference theory and retrieval failure (failure to find).

Interference theory: forgetting occurs because one memory
Interferes with another memory.

Forgetting in Long Term Memory is often explained by interference theory and retrieval failure (failure to find).

Interference theory: forgetting occurs because one memory
Interferes with another memory.

40
Q

explain interference theory

A

According to interference theory, forgetting is caused by two memories competing. There are two forms of interference: proactive and retroactive interference.

Mrs Phillips has difficulty remembering names. She is always mixing up student names past and present. Give examples of the two errors you might expect Mrs Phillips to make according to the interference theory (proactive and retro-active). \

  1. Proactive interference

An old memory interferes with a new memory.

Examples:
Teacher calling younger sibling the name of older sibling

  1. Retroactive interference

A new memory interferes with a old memory.

Examples:
Teacher calling older sibling by younger siblings name

41
Q

study that supports interference theory

A

Research Study: Baddeley & Hitch (1977)

Explain how Baddeley & Hitch’s (page 78) research supports the interference theory.
Made participants remember the names of rugby teams they had played against and it was found that that forgetting was due to number of games played rather than time passed between the games. This supports the interference theory more than decay theory.

Research Study: Schmidt et al. (2000).

Participants were questioned on the street names surrounding a neighborhood in order to measure interference. It was found that there a positive correlation between amount of times moving house and amount of street names that had been forgotten.

42
Q

evaluation of the interference theory

A

It is unclear what the neurological processes underpin interference in our brains

It cannot account for all types of forgetting:

The theory can only explain forgetting when material is learnt simultaneously and /or two sets of material are similar. Forgetting happens over a long period of time and the stimulus that has been forgotten isn’t always related to another stimulus. For example, meaningful / semantic material seem to be resistant to interference

43
Q

explain retrieval failure as an explanation for forgetting

A

One criticism of the interference theory is that much of the research is descriptive; the research doesn’t shed light on the processes involved in interference and memory. Therefore, it is difficult to develop practical applications that will have significant economic benefits e.g. in the treatment of amnesiacs.

Cue dependent forgetting occurs when information is stored in long term memory alongside associated cues. At point of recall, if the cues aren’t present then the information will not be recalled. The information is there, but you cannot access it.

Memory of something is dependent on having the right cues available to recall

Is the absence of prompts to trigger memory’s to be recalled

Being in same state makes it more likely for cues to be able to be recalled

Tulving’s encoding specifically principle states that you are more likely to recall something when you are in and around the same cues (triggers) that you learnt them in the first place. According to Tulving the cues need to be there at the point of learning and recalled.

44
Q

what are the 3 types of cue dependent forgetting? and theorys to supports

A

organization, context and state dependent forgetting.

Organization:
Organization gives a structure which can provide triggers for a memory, e.g. category names.

Tulving & Pearstone (1966)

When given a list of 48 words in 12 categories to learn, participants were told they wouldn’t have to recall the headings, just the words in the categories.

Participants who weren’t given the headings as cues to facilitate recall remembered fewer words that the participants given the headings as cues.

This supports the lack of retrieval cues as an explanation for forgetting.

This supports learning through mind-maps as they increase the number of nodes available to be recalled and therefore make more links between information learnt.

Context dependent failure:

A form of cue dependent forgetting where recall occurs in a different external setting (or emotional state) to learning.

Research study – Godden & Baddeley (1975)

Describe Godden & Baddeley methods, findings and conclusions.

environmental cues do improve recall and supports cue dependent theory

Recall better in the environment it was learned in

50% better recall when learning and recall are the same,
40% more words were forgotten when the condition changed.

Recall for learning on land and recall on land was 13.5 compared to 8.6 when they learned the words on land and had to recall under water.

Increasing the amount of cues in the environment the learning takes place within

State-dependent failure:

A form of cue dependent forgetting where recall under different psychological and physiological states.

Research study – Carter & Cassaday (1998)

Found that when participants were given a light sedative (anti-histamines) while learning a passage of prose their recall was significantly worse when they were asked to asked to recall the prose under ‘normal state’ compared to recall under a sedative state.

45
Q

explain eye witness testimony?

A

Eyewitness testimony is a legal term. It refers to an account given by people of an event they have witnessed.

For example they may be required to give a description at a trial of a robbery or a road accident someone has seen. This includes identification of perpetrators, details of the crime scene etc.

Eyewitness testimony is an important area of research in cognitive psychology and human memory.

Juries tend to pay close attention to eyewitness testimony and generally find it a reliable source of information. However, research into this area has found that eyewitness testimony can be affected by many psychological factors:

Anxiety / Stress
Reconstructive Memory
Weapon Focus
Leading Questions (Loftus and Palmer, 1974)

46
Q

explain anxiety and stress effect on EWT (use studies)

A

Deffenbacher (1983) reviewed 21 studies and found that the stress-performance relationship followed an inverted-U function proposed by the Yerkes Dodson Curve (1908).

This means that for tasks of moderate complexity (such as EWT), performances increases with stress up to an optimal point where it starts to decline.

Clifford and Scott (1978) found that people who saw a film of a violent attack remembered fewer of the 40 items of information about the event than a control group who saw a less stressful version. As witnessing a real crime is probably more stressful than taking part in an experiment, memory accuracy may well be even more affected in real life.

However, a study by Yuille and Cutshall (1986) contradicts the importance of stress in influencing eyewitness memory.

They showed that witnesses of a real life incident (a gun shooting outside a gun shop in Canada) had remarkable accurate memories of a stressful event involving weapons. A thief stole guns and money, but was shot six times and died.

The Yuille and Cutshall study illustrates two important points:

  1. There are cases of real-life recall where memory for an anxious / stressful event is accurate, even some months later.
  2. Misleading questions need not have the same effect as has been found in laboratory studies (e.g. Loftus & Palmer).
47
Q

explain the reconstructive memory in terms of EWT?

A

Bartlett ’s theory of reconstructive memory is crucial to an understanding of the reliability of eyewitness testimony as he suggested that recall is subject to personal interpretation dependent on our learnt or cultural norms and values, and the way we make sense of our world.

Storing information is like recording and remembering is like playing back what was recorded. With information being retrieved in much the same form as it was encoded.

However, memory does not work in this way. It is a feature of human memory that we do not store information exactly as it is presented to us. Rather, people extract from information the gist, or underlying meaning.

In other words, people store information in the way that makes the most sense to them. We make sense of information by trying to fit it into schemas, which are a way of organizing information.

Schemas are mental ‘units’ of knowledge that correspond to frequently encountered people, objects or situations. They allow us to make sense of what we encounter in order that we can predict what is going to happen and what we should do in any given situation. These schemas may, in part, be determined by social values and therefore prejudice.

Schemas are therefore capable of distorting unfamiliar or unconsciously ‘unacceptable’ information in order to ‘fit in’ with our existing knowledge or schemas. This can, therefore, result in unreliable eyewitness testimony.

Bartlett tested this theory using a variety of stories to illustrate that memory is an active process and subject to individual interpretation or construction.

In his famous study ‘War of the Ghosts’, Bartlett (1932) showed that memory is not just a factual recording of what has occurred, but that we make “effort after meaning”. By this, Bartlett meant that we try to fit what we remember with what we really know and understand about the world. As a result, we quite often change our memories so they become more sensible to us.

48
Q

explain weapon focus in relation to EWT

A

This refers to an eyewitness’s concentration on a weapon to the exclusion of other details of a crime. In a crime where a weapon is involved, it is not unusual for a witness to be able to describe the weapon in much more detail than the person holding it.

Loftus et al. (1987) showed participants a series of slides of a customer in a restaurant. In one version the customer was holding a gun, in the other the same customer held a checkbook. Participants who saw the gun version tended to focus on the gun. As a result they were less likely to identify the customer in an identity parade those who had seen the checkbook version

However, a study by Yuille and Cutshall (1986) contradicts the importance of weapon focus in influencing eyewitness memory.