Memory

Memory

• involves the ability to both preserve and recover information we have learned or experienced. 

• refers to the processes that are used to acquire, store, retain and later retrieve information. 

• There are 3 main features of memory; Encoding, Storage and Retrieval – we will consider these throughout this module

Cognitions

the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses, aka; thoughts and memories.

Engram

a memory trace that is stored within the brain and can be extracted when the memory is requested.

Coding

The way in which information is stored / put into / processed into memory, e.g. acoustic, visual, semantic.  eg when information is changed into a form which can be stored.  (via an electrical ‘morse code’).

Capacity

A measure of how much can be held in memory, in terms of bits or chunks of information.

Duration

A measure of how long a memory lasts in a store, before it is no longer available for recall.

Baddley’s (1966) cat/mat study- coding STM

• investigated how information is coded in short term memory 

• inishings for each list were approximately A:10%, B:80%, C:65%, D:70%

• The results show Acoustic confusion- list A was recalled poorly, because the codes of the words were so similar, they became muddled upon recall 

• So it can be concluded that STM coding is done mostly acoustically (we prefer to code words based on sounds)  

Jacobs (1887) serial digit span- capacity STM

• Digit span refers to how many pieces of information the STM can hold at any one time 

• Read out the following list of digits (one at a time) and gradually increase the length of the number sequences. Ask the participants to recall the list and immediately after hearing it 

• The participants must recall the digits correctly. The digit span they reach (before going wrong consistently) is a measure of their STM capacity 

• Jacob’s found that participants could recall digit spans between 5-9 digits in length

• Miller (1956) called this number 'Miller's magic number’: 7+/-2 items

• He found the capacity of STM was the same for different types of items e.g. words, dots, letters and musical notes

• Chunking can help increase the number of items we can hold in STM. This is where we group items into larger units or chunks 

Peterson & Peterson (1959) Trigram retention experiment- Duration STM

• Participants were asked to read a nonsense trigram 

• Immediately on hearing the trigram, participants have to count backwards in 3’s from a large 3 digit number (e.g. 576) for a specific time period 

• This time period was called the retention interval and it varied from 3 to 30 seconds, and was designed to prevent rehearsal of the trigrams 

• At the end of the retention, participants had to try to recall their trigram 

• After 3 seconds= 90% of the trigrams were accurately recalled

• After 18 seconds= 10% of the trigrams were accurately recalled

• After 30 seconds= 0% og the trigrams were accurately recalled 

Trigram

three constants

Coding of long term memory

Baddeley (1966) used the same method as in his STM cat/mat study, but this time gave his participants 20 minutes to learn the word lists. 

Findings:

List A: 70-85%

List B: 70-85%

List C: poorer at 50-60%

List D: 70-85%

Conclusion:

This time there was Semantic Confusion (as list C was recalled the worst) because the codes of the words were so similar, they became muddled up on recall.  

So it can be concluded that LTM coding is done mostly semantically (we prefer to code words based on meaning).

Capacity of long term memory

• unlimited (or infinite)

• The number of items stored in LTM cannot be measured, so there are no studies to test it.

• It cannot be measure as it would be incredibly difficult for a person to recall all the information they can remember 

Duration of long term memory

Bahrick (1975) tested this with his High School Yearbook Study

Procedure: 

• 400 participants (aged 17 to 74) USA.

• Task 1: Free recall: asked to name everyone in their year in high school.

• Task 2: Cued recall: given a set of photos, some of which they went to school with, and some they didn’t; asked to recognize the people they knew.

• Task 3: Cued recall: given a set of names, some of which they went to school with, and some they didn’t; asked to recognize the people they went to school with. 

Findings:

Task 1: Free recall was poor for everyone, irrespective of how long ago they left school.

Tasks 2 & 3:  Those who left school up to 15 years ago; 90% correct recognition of faces and names.

Tasks 2 & 3: Those who left school up to 48 years ago; 80% names and 70% faces.

Conclusion: 

Duration of LTMs is a lifetime, as long as we have cues to help access them.

The multi-store of memory

In 1968, Atkinson and Shiffrin modelled a representation of human memory, describing it in terms of ‘stores’ and ‘loops’. It is known as the multi-store of memory because it consists of 3 memory stores, linked to each other by the processes that transfer information from one store to another 

Description of the model

• Information from our environment enters the Sensory register via the 5 senses.  

• The sensory register acts as a filter; only if attention is paid to the information, it will be transferred to our Short term memory.

• Our Short term memory is where we are consciously aware of the information, but this is only a temporary store.  Information will only last 18-30 seconds, and only 7 +/- 2 items can be held here at any one time. 

• Information must be attended to in the rehearsal loop, if it is to avoid decay or displacement, and so it can be transferred to our long term memory for permanent storage.

• Information will need to be retrieved back to our short term store if it is to be used again. 

AO3 EVALUATION: The multi-store of memory

• Research support- Shallice and warringtons (1970) Case study of KF and Blakemore’s (1988) Case study of Clive Wearing

• Brain scan evidence- Beardsley (1997) found that during tasks involving the use of short term memory, the prefrontal cortex was activated. Squire (1992) found that when carrying out a task using long term memory, the hippocampus was activated

• Machine reductionism-  it attempts to explain a complex behaviour by comparing humans to computers (machines).  However, as memory is a complex phenomenon, highly affected by emotions and motivation, this undermines the complexity of human memory

The working memory model (WMM)

Baddeley and Hitch (1974) argued that memory was more complex than just a ‘stopping off station’ for information to transfer to LTM. They proposed that the STM should be replaced by that of ‘Working Memory’; a system that allows several pieces of information to be processed and interrelated at the same time. Also that information can flow from LTM to STM as well as the other way around. It’s known as ‘Working’ because it is an active store which holds information which is being manipulated and worked upon.

The central executive

• Allocates resources dependent on cognitive demands (like a manager). It controls the other ‘slave’ or component systems 

• Drives the whole system (e.g. the Boss of working memory) and allocates data to the subsystems (VSS & PL) depending on cognitive demands.

• Acts as a filter and determines what information will and will not be attended to. 

• Restricts conscious awareness to 2 (max) items – one from each subsystem only.

Phonological loop

• Is a temporary acoustic storage system for auditory and verbal information that we use to repeat information (e.g. telephone numbers) or store words before we speak (also used in reading). It contains two subsystem: phonological stores and articulatory process

• The phonological store (inner ear) which stores the words you hear for a brief period (also pitch and loudness of sounds).

• The articulatory process (the inner voice) which allows maintenance rehearsal (repeating of words/sounds in a ‘loop’ to keep them in working memory while they are needed).

• It is a temporary acoustic store. Storage here is believed to last 2 seconds only.

Visuo spatial Sketchpad

• Rehearses visual and/or spatial information. It is also called the ‘inner eye’. Logie (1995) sub-divided this store into a visual cache (stores visual information e.g. form and colour) and an inner scribe (stores information about spatial information) 

• It is responsible for setting up and manipulating mental images. 

• Like the phonological loop, it has limited capacity but the limits of the two systems are independent. 

Episodic buffer

• Baddeley later proposed an additional component; the Episodic Buffer.  

• It binds together information from different sources into chunks or ‘episodes’

• One of its other important functions is to recall material from LTM & integrate it into STM when working memory requires it (e.g. imagining an elephant ice-skating).

A03 EVALUATION: The working memory model

• Hitch and Baddeley (1975) Dual Task Experiment- Studies of dual-task performance support the separate existence of the visuo-spatial sketchpad and phonological loop.  Baddeley et al showed that participants had more difficulty doing two visual tasks (tracking a light and describing the letter F) or two verbal tasks, than doing both a visual and verbal (phonological) task at the same time. This increased difficulty is because both visual tasks (dual tasks) compete for the same slave system, whereas, when doing a verbal and visual task simultaneously, there is no competition. This gives support to the separate slave systems (the visuo-spatial sketchpad and phonological loop) that processes the visual input and acoustic input separately, and the theory that the Central Executive can only allow focus on one item from each store at any one time.

• Shallice and Warrington (1970) Case Study of KF- KF’s STM only had problems with verbal items but his visual items were fine. Therefore his phonological loop was disrupted but his visual spatial sketchpad was intact. This suggest that they are two components of the brain and work differently

• Paulescu (1993) Psychological Evidence from PET brain scans- The Working Memory Model is supported by studies involving brain scans.  PET scans have shown that different areas of the brain are used when undertaking verbal and visual tasks (e.g. counting to 20 out loud, or looking at a moving pattern).  The scans are able to distinguish which areas of the brain are used for the visuo-spatial sketchpad and which for the phonological loop.

• Machine reductionism- However, research examining the WMM is an example of machine reductionism as it attempts to explain a complex behaviour by comparing humans to computers (machines).  However, as memory is a complex phenomenon, highly affected by emotions and motivation, this undermines the complexity of human memory and does not provide us with a comprehensive understanding of memory in everyday context, limiting the usefulness of the WMM in explaining human memory accurately.

Long term memory

There are three types of long term memory:

1. episodic

2. semantic

3. procedural

Episodic memory

• Explicit/declarative memories 

• Our ability to recall events (episodes) from our lives. These are personal memories – with reference to time, and the people, objects, places and behaviours involved.

• Memories from our episodic store can be retrieved consciously (explicit memories) and acknowledged.

• Examples: eating breakfast this morning, experiences on your last birthday 

Semantic memory

• Explicit/declarative memories 

• Our knowledge of the world. Including facts and our knowledge of what words and concepts mean.

• Memories from our semantic store can be retrieved consciously (explicit memories) and acknowledged.

• Examples: What you ate for breakfast this morning, what a tree is, what the Multi-store model of memory is.

Procedural memory

• (Implicit/ Non-declarative)

• Our knowledge of how to do things. Our learned practical skills. Muscle memory.

• Memories from our procedural store can not be retrieved consciously (implicit memories), they are done without acknowledgment.

• Examples: handwriting, walking, riding a bike, swimming 

AO3 EVALUATION: Long term memory

• Brain scan evidence- There is evidence from brain scan studies that different types of memory are stored in different areas of the brain. E.g. Tulving (1994) used PET scans to show the prefrontal cortex and large areas of the cerebrum were involved in recalling semantic memories, whereas episodic memories can be found in the hippocampus. The procedural memories are found in the cerebellum. This supports the view that there is a physical reality to the different types of LTM, adding validity to the theory.

• Blakemore’s (1988) case study of Clive Wearing- Clive damaged his hippocampus with the virus he contracted. He lost his personal (episodic) memories, but not his semantic (he still knew what objects were and could still use language) or his procedural (he could still handwrite, walk and play the piano, etc) memories. This supports that these types of LTM are located in different areas of the brain, and damage to specific areas of the brain damages only one type of LTM. Adding validity to the theory.

• Idiographic- Research into the different types of LTM have typically been conducted on individual patients and can be considered idiographic in nature. For example, the research into Clive Wearing and HM are highly detailed and provide a lot of information but are fundamentally isolated cases of one individual’s long-term memory damage. This is a weakness because the findings cannot be generalised beyond the research. It would be inappropriate to assume that everyone’s LTM is formed in the same way based on evidence of two case studies. This means that while informative, the research findings can’t be generalised beyond the research, but does provide a good solid basis on which further research can be conducted. 

What is forgetting?

• an extremely useful process since a lot of what we learn we don’t need to remember indefinitely.

• can occur at the encoding, storage or retrieval stage.

• A distinction needs to be made between availability (whether the material is stored in the first place) and accessibility (whether we can retrieve that which is stored).

What are the two explanations of forgetting?

1. interference

2. retrieval failure

Inference

• This form of forgetting occurs when one memory disrupts our ability to recall another.  

• This will only occur when the two memories are similar.

Retroactive inference

• Retro = to move back in time

• Occurs when newly acquired information inhibits our ability to recall previously acquired similar information, (the newer info will override the older info).

• EXAMPLE: In school, you are less likely to remember the material from the beginning of the year than that from the end of the year.

Proactive inference

• Pro = to move forward

• The tendency for previously acquired material to hinder recall of subsequent/current similar information, (the older info will override the newer info).

• EXAMPLE: Entering your old password instead of your current one when you’ve recently changed it.

AO3: Evidence for inference as an explanation of forgetting

McGeoch & McDonald (1931) similarity of items in inference 

• Group 1: Ask your participants to learn Adjective list one, until they can recall them perfectly, then rest for 10 minutes quietly before recalling the list.

• Group 2: Ask your participants to learn Adjective list One, until they can recall them perfectly, then learn 10 3 digit numbers (Number List One) for 10 minutes, and then ask them to recall Adjective List One.

• Group 3: Ask your participants to learn Adjective list One, until they can recall them perfectly, then learn Adjective List Two for 10 minutes, and then ask them to recall Adjective List One.

• McGeoch and McDonald (1931) found that Group 1 participants remembered 4.51 adjectives with the 10 minute rest, Group 2 participants remembered 3.68 with the number interference task and Group 3 only 1.25 words

• This shows retroactive interference 

There is research support for inference in LTM. For example, McGeoch and Mcdonald (1931) conducted a method in which participants were asked to learn adjectives in a list and recall. There were three different group conditions with different participants in each condition. Group 1 had a mean value of 4.51 words accurately recalled whereas Group 3 had a mean value of 1.25. This supports retroactive interference as an explanation of forgetting as the new list stopped them from remembering the old list. 

Retrieval failure

a form of forgetting that occurs when we don’t have the necessary cues to access a memory.  The memory is available, but not accessible unless a suitable cue is provided. 

Cue

is a trigger of information that allows us to access memory.  Such cues may be indirectly linked by being coded at the time of learning.  For example, cues may be external (environmental) or internal (personal, mood or sobriety).

Tulving’s Encoding Specificity Principle:

• If a cue is to help us recall information it has to be present at encoding and at retrxieval.  

• Common cues encoded at the time of learning include context (environmental/external) cues and State (internal) cues. The absence of these cues on recall of information can lead to:

1. Context-dependent forgetting

2. State-dependent forgetting.

Context dependent forgetting

This occurs due to a lack of the correct environmental (or external) cues.

A03 Godden & Baddeley (1975) Underwater Divers Experiment

• Aim: To investigate the effects of context cues on recall. To see whether words learned in the same environment they are recalled in are recalled better than in a different environment to learning. 

• Procedure: 18 diving club participants took part in a repeated measures design consisting of 4 conditions – learning words on land and recalling on land, learning words on land, recalling under water; learning under water recalling under water, learning under water, recalling on land. The underwater condition this was at 20 ft below the surface. Pps had to learn 38 unrelated words which they heard twice during the learning stage. 

• Findings: Around 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 underwater.     

• Conclusion: environmental cues do improve recall and the study supports the theory of context dependent forgetting.

State dependent forgetting 

This occurs due to the lack of the correct personal (or internal) cues.

AO3 Carter & Cassaday’s (1998) Recall Experiment

They gave pps antihistamine drugs (a sedative effect – a drowsy internal state).  The pps then had to learn lists of words and passages of prose and then recall the information, in one of the following conditions:

• Learn drowsy – recall drowsy

• Learn drowsy – recall alert

• Learn alert – recall drowsy

• Learn alert – recall alert

Conditions where there was a mismatch between state cues were recalled the poorest . Thus supporting the theory of state-dependent forgetting. 

AO3 POINT: Determinism

Don’t have control over our own behaviour so we wouldn’t have control over what we forget and what we remember. The explanations of forgetting, such as cue, suggests we may not have control over internal and external cues but we may have techniques to help us remember certain things 

AO3 POINT: Recall versus recognition 

One limitation is that context effects may depend substantially on the type of memory being tested. Godden and Baddeley (1980) replicated their underwater experiment but used a recognition test instead of recall- participants have to say whether they recognised a word read to them from a list, instead of retrieving it for themselves. When recognition was tested there was no context-dependent effect, performance was the same on all four conditions. This suggests that retrieval failure is a limited explanation for forgetting because it only applies when a person has to recall information rather than recognise it 

Eye witness testimony’s

the evidence provided in court by a person who witnessed a crime, with a view to identifying the perpetrator of the crime.

Factors Affecting the Accuracy of EyeWitness Testimony (EWT)

1. leading questions

2. misleading information

3. post evidence discussion

4. Anxiety

Leading questions

• Questions that make it likely that a participants schema will influence them to give a desired answer 

• E.g. exaggerating the truth 

• For example; how fast was the car driving when it smashed/bumped

Misleading information

• Incorrect information given to the eyewitness that may alter a memory after the event. Information that suggest a desired response

• E.g. causing a lie 

• For example; what colour was the man’s tie

Post event discussion

• A misleading conversation after an incident has occurred that may alter a witness information added to a memory after an event has occurred

• E.g. contaminating a memory 

• For example; discussing what you have seen with other people or other witnesses 

The Effect of Leading Questions on the Accuracy of Eye-Witness Testimony

Loftus & Palmer’s (1974) Leading Questions Bumped/Smashed Experiment

Experiment 1:

• 45 student participants were put into groups and shown short films involving car accidents. After each film they were shown, they were given a questionnaire to fill in, where only one question was critical: estimation of the speed that the cars were travelling at. There were five different conditions for this experiment, which differed only by the phrasing of the critical question. In one group, participants were asked “how fast do you think the cars were travelling when they hit each other”, and another was asked “how fast do you think the cars were travelling when they smashed into each other”. The only word that differed between the groups was the choice of verb. Apart from ‘hit’ and ‘smashed’, the words ‘collided’, ‘bumped’ and ‘contacted’ were used. Altogether, there were seven films shown to the participants. In order to get a precise series of results, the average estimation was taken for each participant group.

Findings:

Loftus and Palmer found significant differences between the average estimates depending upon the severity of the verb:

• ‘smashed’ gave an average estimate of 40.8mph

• ‘collided’ gave an average estimate of 39.3mph

• ‘bumped’ gave an average estimate of 38.1mph

• ‘hit’ gave an average estimate of 34.0mph

• ‘contacted’ gave an average estimate of 31.8mph

Conclusions:

• The more extreme the verb was in the question, the higher the average estimation of the cars’ travelling speeds.

• This allowed Loftus and Palmer to conclude that leading questions did have an effect on eyewitnesses' accuracy of recall.

The Effect of Misleading Information on the Accuracy of Eye-Witness Testimony

Loftus and Palmer (1975) Misleading Information Experiment:

Experiment 2: 

• New participants watched a video of a car accident and were asked similar ‘speed’ questions to Experiment 1. A week later some participants were also asked “Did you see the broken glass?”. There was no broken glass in the video, but more participants in the ‘smashed’ condition reported seeing some.

Conclusion: 

• Loftus and Palmer concluded that the phrasing of the questions had a clear effect on witnesses’ answers and therefore that leading questions and misleading information can affect the way that eyewitnesses respond.

AO3- ecological validity (loftus and palmer 1974/75)

• Watching the accident on a video and not in real life, not actually seeing it happening before them. Therefore, participants may not react in the same way to the crash and they may not view it as serious and therefore be less accurate in their estimations. Schema fills in the details rather than our actual memory 

• Because they are being asked in a questionnaire and not in real life by someone like a police office, they may not be as accurate in their answers

• Demand characteristics- participants know they are being tested on memory so may be more alert and give better answers

Loftus and Pickerell’s (2002) Bugs Bunny in Disneyland Experiment

• Tried to get people to ember they met with bugs bunny at disneyland 

• However, Bugs bunny is a warner brothers character and so wouldn't be at the disney park

• Gave participants a fake ad for disney and asked them to review it. The ad included a picture of Bugs bunny 

• As part of the review, participants were asked about their trips to disney and if they saw bugs bunny 

• They found that lots of the participants said they met Bugs and they took pictures with him etc. Participants could even recall details about their encounter. 

• Misleading information kicks in our schema to fill in the details and remembers traits of Bugs Bunny 

Yuille and Cutshall (1986) Case Study of a Real Life Crime

A study suggesting EWT is not affected by post event misleading information

• This research involved an investigation into a real life shooting incident in the middle of a busy street in Vancouver, Canada.  A thief had entered a gun shop, tied up the owner and stolen some money and a number of guns.  The store owner managed to free himself, pick up a revolver and went outside to take the thief’s licence number.  However, the thief had not yet entered his car and fired two shots at the owner.  After a slight pause the owner fired all six shots from his revolver.  The thief was killed, but the owner recovered from all his injuries.

• 21 witnesses observed the shooting incident in which one person was killed and a second seriously injured.  All of the witnesses were interviewed by the police and 13 agreed to a research interview 4 to 5 months after the incident (to test the effects of post-event discussion).  The researchers also asked leading questions and misleading questions based on Loftus’ research.

Findings:

• They found that most witnesses were highly accurate in their accounts and there was little change in the amount or accuracy of recall over the 5 month intervening period.  

• Leading questions, misleading information and post-event discussion was found to have no effect on real-life witness accounts.

AO3- experimental reductionism (research into factors effecting EWT)

However, research examining the EWT is an example of experimental reductionism, as it attempts to explain a complex behaviour by relying on isolated variables, operationalised in laboratory experiments such as how leading questions might affect the estimation of speed.  However, as memory is a complex phenomenon, multiple factors may interact and have an effect on memory, for example personality factors may affect leading questions. Many psychologists argue that reducing memory to isolated variables undermines the complexity of human memory and does not provide us with a comprehensive understanding of memory in everyday context, limiting the usefulness of the EWT in explaining human memory accurately.

Anxiety

• Anxiety may be an even more significant contributor to the inaccuracy of eye-witness testimony.  

• Crimes tend to cause high levels of anxiety (fast paced, loud, frightening experiences – even to the witness), which in turn can cause memories to distort.

The Yerkes-Dodson Inverted-U Hypothesis

The Yerkes-Dodson effect shows that arousal has a negative effect on the accuracy of eyewitness recall when it is at very low levels, or very high levels.  But moderate levels of anxiety/arousal are actually very beneficial to accuracy of recall as adrenaline can sharpen our senses and create clearer memories.

Negative effects of anxiety on EWT

Too much anxiety can lead to a sensory shut down, leading to less attention paid and less accurate recall

Positive effects of anxiety on EWT

The right amount of anxiety (peak) leads to more attention paid and more accurate recall

Johnson and Scott (1976)  The Weapon Effect Experiment (negative effects of anxiety)

• Procedure: Participants were waiting outside a laboratory overhearing an exchange between people in the adjacent room. In one condition a man with greasy hands storms out of the room holding a pen (low anxiety condition), while in the other condition a man emerged holding a knife covered with blood (high anxiety – weapon focus condition). Participants were later asked to identify the person out of a set of photos. 

• Findings: Participants in the pen condition were more accurate in recognising the man. 49% recognition in pen condition compared to 33% in the knife condition.

• Conclusion: It is believed that the anxiety elicited by the weapon (blood-stained knife) narrowed the focus of attention, which reduces the amount of information and detail beyond focussing on the weapon.  Any memories of further detail of the crime and perpetrator will be weak, therefore reducing the accuracy of the eye-witness’ testimony.

Yuille and Cutshall (1986) Case Study of a Real Life Crime (positive effects of anxiety)

• (Same experiment as before) 

• People in Yuille and Cutshall’s study were in a highly anxious situation and were still able to accurately recall the events 

Improving the accuracy of eyewitness testimony 

accuracy is vital to the police and the courts.

So Psychologists have turned their attention to finding ways of improving the accuracy of EWT based on psychological evidence.

Cognitive interview

a police technique for interviewing witnesses to a crime which encourages them to recreate the original context of the crime in order to increase the accessibility of stored information. Because of our memory is made up of a network of associations rather than of discrete events memories are accessed using multiple retrieval strategies

Fisher and Geiselman (1992)

argued that EWT could be improved if the police used better techniques when interviewing witnesses.  These techniques are based on existing theories of memory and forgetting.

1. report everything

2. Reinstatement of Context

3. reverse the order

4. change perspective

Report Everything

witnesses are encouraged to include every single detail of the event (including their own thoughts and feelings), even if it may seem irrelevant. These may trigger other important memories.

Reinstatement of Context

returning to the scene of the crime (to use the context and state cues available there).  Or to imagine being back at the scene.

Reverse the order

recall events of the crime in a different order e.g. backwards.  This will remove the expectations and ‘gap filling’ (schema effects) of a story told in an order that should flow and make sense.

Change Perspective

recall the incident from someone else’s (or something else’s) perspective at the scene of the crime. Another way of disrupting a person’s schema.

The Enhanced Cognitive Interview

Fisher (1987) developed some additional elements of the Cognitive Interview to help develop the social dynamics of the interview interaction:

• Reducing eyewitness anxiety 

• Minimising distractions

• Asking the witness to speak slowly

• Asking open ended questions

Police interview vs cognitive interview

Police interview	Cognitive interview
Questioning approach is structured and direct  Aimed at obtaining concise and targeted information from the witness or victim  Close-ended questions that elicit brief responses  Emphasis on gathering essential details relevant to the investigation	Focus is to make witness and victims of a situation aware of all the events that transpired  More open-ended and non direct questioning approach  Eliciting as much information as possible, even if irrelevant

AO3 Evaluation: the effectiveness of the cognitive interview 

• Fisher and Geiselman (1989) The Use of the Cognitive Interview: 16 experienced police interviewers conducted two interviews on 47 witnesses of victims of shoplifting or mugging.  All first interviews were standard police interviews. Between the two interviews, seven of the police officers were trained in using the cognitive interview technique.  The other nine officers formed the control group (who would interview the witnesses again using another standard interview).  The researchers measured both the increase in facts elicited in the second interview compared to the first, and the number of facts elicited by the police officers in the cognitive interview compared to the control group.   The IV was the type of second interview used (cognitive or standard) and the DV was the number of accurately recalled facts. Findings: Results provided overwhelming support for the benefits of using the cognitive interviewing technique.  The cognitive interviewers obtained 47% more facts about the crime, compared to no increase in facts from the second interview if it was another standard police interview.

• Support for the effectiveness of cognitive interview: a meta analysis by Gunter Kohnken et al (1999) combines data from 55 studies comparing the cognitive interview (and the enhanced cognitive interview) with the standard police interview. The ci have an average of 41% increase in accurate information compared with the standard interview. Only 4 studies in the analysis showed no difference between the types of interview. This shows that the CI is an effective technique in  helping witnesses to recall information that is stored in memory (available) but not accessible

• Some elements may be more useful: Rebecca Milne and Ray Bull (2002) found that each of the 4 techniques used alone produced more information than the standard police interview. But they also found that using a combination of report everything and reinstate the context produced better recall than any of the other elements or combination of them. This confirmed police officers' suspicions that some aspects of the CI are more useful than others. This casts some doubt on the credibility of the overall cognitive interview 

• Cognitive interview is time consuming: Police officers may be reluctant to use the CI because it takes more time and training than the standard police interview. For example, more time is needed to establish rapport with a witness and allow them to relax. The CI also requires special training and many forces do not have the resources to provide more than a few hours (Kebbell and Wagstaff 1997). This suggest that the complete CI as it exists is not a realistic method for police officers to use and it might be better to focus on just a few key elements