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Flashcards in memory Deck (9)
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Code, capacity and duration of memory

Study 1: Baddely (1966)
Acoustically similar words eg: cat and cab
Acoustically dissimilar words eg: pit and few
Semantically similar words eg: large and big
Semantically dissimilar words eg: good and hot
STM is acoustic
LTM is semantic

Study 2: Jacobs(1887)
Digit span: researchers read 4 digits and increase until the participants cannot recall the order correctly
Participants on average could recall back 9.3numbers and 7.3 letters in the correct order

Study 3: Miller (1956)
Miller made observations of everyday practice eg: noted things that come up in 7s
The span of STM IS ABOUT 7 ITEMS +OR- 2 but can be improved using chunking

Study 4: Peterson and Peterson (1959)
Duration during STM
24 students were given a consonant syllable to remember and a 3- digit number to count backward for (multiple of 3) seconds
Students recalled 80% of syllables correctly with 3 seconds interval
Average recall after 18 seconds fell 3%
suggests a duration of SLM without rehearsal is 18-30 seconds

Study 5: Bahrick et al
Participants were 392 Americans aged 17-74
1)recognition test: 50 photos from participants high school yearbook
2)Free recall test: Participants listed names of graduating class
Participants tested from 48years after graduation were 70% accurate on the recognition test. Free recall was less accurate

Code, capacity and duration of memory

-ve = It didn't use meaningful material (study 1)
The words used had no personal meaning
When processing meaningful information people use semantic coding even for STM task
Should be cautious of generalizing results

-ve = It may have overestimated the capacity if STM (study 3)
A researcher reviewed other research
He concluded the capacity of STM was only about 4 chunks
The results may not be valid because of confounding variables that weren't controlled

+ve = It has high external validity
Real life meaningful memories were studied


The multi-store model of memory
Atkinson and Shiffrin (1968) multistore model (MSM)
The MSM describes how information flows through the memory system
Stimulus from the environment goes to the sensory register and then goes short term memory followed by long term memory
A stimulus from the environment passes into the Sensory register along with lots of other sights, sounds, etc
.Duration- very brief (less than half a second)
.Capacity- high
.Coding- Depends on the sense - visual, auditory, etc

Transfer from SR to STM
Little of what goes into the SR passes further (needs attention to be paid for it)

Short term memory (STM) - STM is a limited capacity and duration store
.Duration: About 18 to 30 seconds unless it's rehearsed
.Capacity: Between 5 and 9 items before some forgetting occurs
.Code- acoustic

Transfer from STM to LTM
Maintenance rehearsal occurs when we repeat material to ourselves.
We can keep information in STM as long as we rehearse it
If we rehearse it long enough, it passes into LTM

Long-term memory (LTM)
A permanent memory store
When we want to recall material stored in LTM it transfers back the STM by a process known as retrieval
1)Duration: potentially up to a lifetime
2)Capacity: Potentially unlimited
3)Coding: tends to be in terms of meaning (semantic)

The multi-store model of memory
+ve - supported by research showing STM and LTM are different
Baddley found that we tend to mix words when using STMs
But we mix similar words when using the LTMs
Proves coding in STM is acoustic and Coding in LTM is semantic

-ve - It only explains one type of rehearsal
Researchers argued there's to types if rehearsal: maintenance and elaborative
Maintenance was the only one discussed in MSM
Elaborative rehearsal is needed for LTM
A serious limitation of MSM because it's another research finding that cannot be explained by the model

-ve - It oversimplifies LTM
There's a lot of research evidence that LTM is not a unitary store
We have a semantic and episodic as stores if memories
MSM doesn't reflect these types of LTM


Types of long-term memory
LTM store 1: Episodic memory
Stores events from our lives
(like a diary if daily happenings)
They are complex as they are time stamped and involve several elements eg people, places, objects, etc

LTM store 2: Semantic memory
Stores our knowledge of the world
It includes knowledge on how things taste and meaning of words etc
semantic memories are not time stamped and is less personal but more about the knowledge we share

LTM store 3: Procedural memory
Stores memories for action and skills
These are memories for how we do things
These are the sort of memories we may find hard to explain to someone as we recall these memories without conscious awareness (eg: Riding a bike)

Types of long-term memory
+ve - episodic memory is supported by case studies
Clinical studies and amnesia shows both difficulties recalling events that had happened to them in the past
Both their semantic memories were unaffected
This supports the view that there is more than one memory store in the LTM

-ve - There are problems with clinical evidence
Evidence is often based on one clinical case about what happens when memory is damaged
There's a serious lack of control of different variable in these studies
It's difficult to generalise from these case studies

+ve - Brain scan studies show that there are different LTM stores
Researches had participants perform memory tasks while their brains were scanned with a PET scanner
Episodic and semantic memories were in the prefrontal cortex
Semantic on the left side and Episodic on the right prefrontal cortex
Shows a physical reality in the brain to the different types of LTM


The working memory model (WMM)
Baddeley and hitch (1974)
WMM is concerned with the part of the mind that is active when working on arithmetic problems or playing chess or comprehending language
Central executive (CE) allocates slave systems
It has a very limited storage capacity
Phonological loop (PL) consists of a phenological store and an articulatory process
PL deals with auditory information and preserves the order in which information arrives
It's subdivided into:
1)Phonological store - stores visual data
2)Articulatory process - allows maintenance rehearsal
Visuo-spatial sketchpad (VSS)
Stores visual or spatial information when required
Logie (1995) subdivided the VSS into:
Visual cache: stores visual data
Inner scribe: Records arrangement of objects in the visual field
Episodic buffer (EP) Temporary storage
Integrates visual, spatial and verbal information from other stores
Maintains a sense of time sequencing (records events happening)
Links to LTM

The working memory model (WMM)

+ve = Dual-task performances studies support the VSS
Baddeley found participants had more difficulty doing two visual tasks than doing one visual and one verbal task at the same time
Because both visual tasks compete for the same limited resources

-ve = WMM lacks clarity over the central executive
Cognitive psychologists suggest The CE is unsatisfactory and doesn't really explain anything
The CE should be more clearly specified
WMM hasn't fully been explained

+ve = Word length effect supports the phonological loop
Baddeley found people have more difficulties remembering a list of long words than a list of short words
This is because there's limited space for rehearsal in the articulatory process
Word length tasks disappear when rehearsal tasks are given


The explanation for forgetting: interference
Interference theory
The inference is when two pieces of information are in conflict
Forgetting occurs in LTM as we can't get access t memories even though they are available
Proactive interference (PI) -old interferes with new
Eg: Teacher learns many names in the past and can't remember the names of her current class
Retrieve interference (RI) -New interferes with old
Eg: A teacher learns many new names this year and can't remember the names of her current students
Interference is worse when memories are similar
This may be because:
.In PI previously stores information makes new information more difficult to store
.In RI new information overwrites previous memories which are similar
Key study: McGeoch and McDonald (1931) Effects of similarity
Procedure: Participants were asked to learn a list of words
Then they were given a list of new words to learn
Group 1: Synonyms-words have the same meaning as the originals
Group2: antonyms - words with an opposite meaning to the originals
Group3: Unrelated - words unrelated to the original ones
Group 4: Consonant syllables
Group 5: Three- digit numbers
Group 6: No new list
Performance depends on nature of seocns list (most similar words =worst recall)
This shows interference is strongest when the memories are similar

The explanation for forgetting: interference
-ve - The use of artificial materials
The stimulus material used is often word lists
This is more realistic than consonant syllables
eg: In everyday life, we remember peoples faces, their birthday, etc
Use of artificial material makes interference much more likely in the lab

+ve - real-life studies gave supported the interference explanation
Baddeley and hitch had asked rugby players to recall the names of teams they had played so far in the season
The accurate recall didn't depend on how long ago the match took place
This shows interference explanation can apply to at least some everyday situations

-ve - time allowed between learning
Research reduces the whole experience of learning into a short time period which doesn't reflect how we learn and remember most information in real life
Cannot be generalized outside the lab


Explanation for forgetting: retrieval failure
Retrieval failure due to the absence of cues
Lack of cues can cause retrieval failure
When information is initially placed in the memory, associated cues are stored at the same time
If the cues are not available at the time of recall, you may not be able to access memories that are actually there

Encoding Specific Principle (ESP)
Tulving suggests that cues help retrieval if the same cues are present at encoding and at retrieval
The closer the retrieval cue to the original cue, the better the cues work
Some cues have meaning linked to the memory
Some cues are linked to the material-to-be-remembered in a meaningful way
eg: The cue STM may lead to recall about short term memory
Some cues have no meaningful links
Other cues are also encoded in the time of learning but not in a meaningful way
.Context-dependent forgetting - When memory retrieval is dependant on an external/environmental cue
.State-dependent forgetting - When memory retrieval is dependant on an internal cue, state of mind

Key study: Godden and Baddeley (1975)
Cues were the contexts where learning and recall took place -On land or underwater
Group 1: Learn on land -recall on land
Group 2: Learn on land -recall underwater
Group 3: Learn underwater -recall on land
Group4: Learn underwater -recall underwater

Findings and conclusion
When the environmental contexts of learning and recall did not match accurate recall was 40% lower than when it did not match
When external cues available at learning were different from ones at recall, this led to retreival failure due to lack of cues
This study demonstrates context-dependant forgetting as information want accessible when context and recall did not match context at learning

Explanation for forgetting: retrieval failure

+ve - evidence supports the explanation of forgetting
Godden and Baddeley's research with deep sea divers
Researcher argues that retrieval failure is perhaps the main reason for forgetting in LTM
Supporting evidence increases the validity

-ve - context effects only occur when memory is tested in certain ways
Godden and Baddeley replicated their underwater experiment using a recognition test instead of recall
There was no context-dependent effect
The performance was the same in all four conditions whether the environmental contexts for learning and recall matched or not
This limits retrieval failure as an explanation for forgetting

-ve - ESP can't be tested and leads to circular reasoning
When a cue produces successful recall of a word, we assume the cue must've been present at the time of learning
If a cue doesn't result in a successful recall, then we assume that the cue was not encoded at the time of learning
There's no way to independently establish whether or not the cue has really been encoded


Eyewitness testimony - Misleading information
Leading questions
Response-bias explanation
The wording of the question has no enduring effect on an eyewitness's memory of an event
It influences the kind of answer given
Substitution explanation
The wording of a question does not affect eyewitness memory; it interferes with its original memory, distorting its accuracy
Key study 1: Loftus and Palmer (1974) leading questions
45 Participants (students) watched film clips of a car accident and ten answered questions about speed
Critical question: 'About how fast were the cars going when they hit each other'
5 groups of participants, each given a different verb in the critical question: Hit, contacted, bumped, collided or smashed
Finding and conclusions:
The verb 'contacted' produced a mean estimated speed of 31.8mph for the verb 'smashed', the mean was 40.5mph
The leading question biased eyewitness recall of an event. The verb 'smashed' suggests a faster speed of the car than 'contacted'
Post-event discussion (PED)
Memory contamination - When co-witness discuss a crime, they mix information from other witnesses with their own memories
Memory conformity- Witnesses go along with each other to win social approval or because they believe the other witnesses are right
Key study 2: Gabbert et al (2003)Post-event discussion
Procedure :
Paired Participants watched a video of the same crime, but filmed so each participant could see elements in the event the other could not
Both participants discussed what they had seen on the video before individually completing a test of recall
Findings and conclusions
71% of the participants mistakenly recalled aspects of the event that they did not see in the video but had picked up from the post-event discussion
In a control group, where there was o discussion, there were no errors

Eyewitness testimony - Misleading information

-ve - Loftus and palmers study used artificial material
Participants watched film clips of accidents
difficult experience from witnessing a real accident
Researcher found that witnesses of a traumatic real armed robbery had a very accurate recall after four months
Using artificial tasks tell us little about how leading questions affect EWT in real crimes or accidents

-ve - There may be individual differences in accuracy of EWT
Reaserchers found that older people were less accurate than young people when recalling eyewitness reports
They also found that all age groups were more accurate when identifying people of their own age group
Researchers often use young people as the target age to identify

+ve - Research into misleading information has real-life applications
The research has led to important practical uses for police officers and investigators because the consequences of inaccurate EWT can be very serious
Loftus claimed that leading questions can have such a distorting influence on memory that police officers need to be careful about the phrase being used when interviewing the witness


Eyewitness testimony-anxiety
Study 1: Johnson and Scott (1976) Anxiety has a negative effect
Each participant heard an argument in the next room
.Low-anxiety conditions: A man then walked through the waiting room carrying a pen with grease in his hands
.High-anxiety conditions: The heated argument was accompanied by a sound of breaking glass. A man walked out of the room holding a paper knife covered in blood
Participants were later asked for pick the man from a set of 50 photographs
Findings and conclusion:
49% of participants in the low-anxiety condition were able to identify them. The corresponding figure for high-anxiety participants was just 33%
Study 2: Yuille and Cutshall (1986)Anxiety has a positive effect
In a real-life crime, a gun-shop owner shot a thief dead. There were 21 witnesses, 13 agreed to participate in the study
Participants were interviewed 4-5 months after the incident
Accounts were compared to the police interviews at the time of the shootings
witnesses rated how stressed they felt at the time of the incident
Findings and conclusions
Witnesses were very accurate and there was little change after 5 months.some details were less accurate
Participants who reported the highest level of stress were the most accurate
Explaining the contradictory findings
'Inverted U '
Yerkes and Dodson argues that the relationship between performance and arousal/stress is curvilinear rather than linear
Affects memory
Deffenbacher (1983) found that lower levels of anxiety did produce lower levels of recall accuracy
Recall accuracy increases anxiety up to an optimal point

Eyewitness testimony-anxiety

-ve - Johnson and Scotts study may test surprise not anxiety
Participants may focus on a weapon because they are surprised rather than because they are scared
So the weapon focus effect is due to unusualness rather than anxiety, therefore, tells us nothing specific about the effects of anxiety on EWT

-ve - They lack control of variables
Real-life witnesses are interviewed sometime after the event. Many things happen to them in the meantime that researchers cannot control
These extraneous variables may be responsible for the inaccuracy of recall, not anxiety

-ve - 'Inverted U' is too simplistic
Anxiety is difficult to measure as it has many elements - cognitive, behavioral, emotional and physical
It assumes that one of these is linked to poor performances physiological arousal
The explanations fail to account for factors such as fear terror on the accuracy of memory


Eyewitness testimony: The cognitive interview (CI)
1)Report everything
Witnesses are encouraged to add every detail of an event, even if t seems irrelevant o the witness is not confident about it

2)Reinstate the context
Witness returns to the original crime scene and imagines the environment and their emotions
Cues from context may trigger a recall

3)Reverse the order
Events are recalled in a different chronological order
Prevents people from using their expectations of how the event must have happened rather than the actual event
It also prevents dishonesty

4)Change perspective
Witnesses recall the incident from other peoples perspective
How would it have appeared to another witness
This prevents the influence of expectations and schema
on recall
Schema are packages of information developed through experience

5)Enhanced cognitive interview
Fisher et al developed an additional element of the CI
This includes a focus on the social dynamics of the interactions
The enhanced CI also includes ideas such as reducing eyewitness's anxiety
getting witnesses to speak slowly and open-ended questions

Eyewitness testimony: The cognitive interview (CI)

+ve - Some elements of the full CI are useful
Researchers found that each individual element of the CI was equally valuable
However, they also found that a combination of 'report everything' and 'context reinstatement' produced better recall than any of the other technical individuality
So at least these two elements should be used to improve police interviewing of eyewitnesses even if the full CI isn't used

+ve - Support for the effectiveness of the enhanced CI
A meta-analysis combined data from 50 studies
Enhanced CI consistently provided more correct information than the standard interview used by police
Studies like this indicate that there's a real practical benefit to the place of using the enhanced version of CI

-ve - Research may be unrealistic because of variations of the CI
Studies on the effectiveness of CI use slightly different techniques
Different researchers may use variations on the CI or enhanced CI, and police forces evolve their own methods
This means it's difficult to draw conclusions about the CI In general