Memory Flashcards
(13 cards)
Multi-Store Memory Model; proposed by Atkinson and Shiffrin (1968)
is a representation of how memory works in terms of the three stores called Sensory Register, Short Term Memory, and Long Term Memory. Also, it describes how information is transferred, forgotten and remembered.
1) Sensory Register is a store for each of our 5 senses. A stimulus from the environment will pass into the Sensory Register. The two main stores are called iconic (visual) and echoic (auditory) memory. Material lasts for less than half a second but the store has a high capacity. The key to getting the material passed on onto the STM store is attention.
2) STM is a limited capacity store (7+/-2 items, suggested by Miller in 1956) in which material lasts about 30 seconds and is coded acoustically. In order for information to be passed on onto the LTM store, maintenance rehearsal must occur. This is when we repeat material to ourselves.
3) LTM is an unlimited capacity memory store in which information is coded semantically and can last for a very long time. (Bahrick et al 1975 study support this). Retrieval is the process of information being transferred back to the STM store for short term use.
Evaluation
1) A strength of the model is that it is supported by evidence from clinical amnesiacs - which is based on real life rather than experiments, therefore more ecologically valid. For example, HM underwent brain surgery to cure severe epilepsy but this resulted in the inability to transfer information from the STM to the LTM so he could no longer form long-term memories. This supports the model’s concept that there are separate memory stores
2) The model has a too simple explanation of a complex process because it explains little about STM and LTM. also, merely describing them as fixed structures and doesn’t take into account, for example, that there are different types of LTM, proposed by Tulving 1985
3) Much of the scientific evidence which supports the model lacks validity because it is carried out in a lab. This is an artificial environment and also material participants have to remember is unlike information we have to remember in everyday life. Example, trigrams. So the results cannot be applied to real life
4) Glanzer and Cunitz (1966) showed that if you give participants a list of 20 words that are presented at one time and then ask them to recall any words they can remember, they tend to remember the words from the start (primary effect) and the words at the end (recency effect). They were less good at recalling words in the middle of the list.
This shows that there are different memory stores in which different words enter a different store.
5) Shallice and Warrington (1970) studied a patient called KF who suffered from amnesia. They found that his STM for digits was very poor when they read them aloud to him. However, his recall was much better when he was able to read the digits himself.
This is a weakness of the model as the MSM has a unitary store for STM so KF’s inability to process auditory information suggests that there must be more than one type of STM store. (WMM)
6) Baddeley (1966) shows that LTM and STM are qualitatively different. He found that we tend to mix words up if they sound similar when using STM. But for LTM we tend to mix up words that are semantically similar. This supports the MSM’s view that the stores are separate and different.
7) Craik and Watkins (1973) discovered that there are two types of rehearsals. Maintenance rehearsal, described in the MSM, but they believe it doesn’t transfer information from the STM to LTM, it just maintains information in the STM. Elaborative rehearsal is needed for long-term storage. Thia occurs when you link the information to your existing knowledge. This is a weakness because the MSM states that all that matters in rehearsal is the amount you do. The more you rehearse, the more likely it is to transfer to the LTM store and remember it long-term.
Types of Long Term Memory; proposed by Tulving (1985)
Tulving proposed that LTM had three stores that contain different types of material and information.
1) Episodic Memory is the store for recalling personal events. This includes when the memory occurred, the people involved, the objects, places and behaviours involved.
These memories are time stamped so we can remember when they happened.
They have to be recalled consciously and with effort.
2) Semantic Memory is the store for our knowledge of the world. This includes facts, knowledge of what words and concepts mean.
These memories need to be recalled deliberately.
These memories are not time-stamped.
3) Procedural Memory is the store for our knowledge on how to do things and our learned skills.
We can recall without conscious awareness or effort.
For example, driving a car.
Evaluation
1) Case studies of HM & Clive Wearing.
Episodic memory was impaired, as a result of amnesia. They had difficulty recalling past events. However, their procedural memory was still intact - they still knew how to tie their shoelaces, walk and talk. This supports Tulving’s theory of LTM having different long-term memory stores for different type of information
2) The debate on the number of types of LTM
Cohen and Squire (1980) disagreed with Tulving’s division of LTM into 3. They accept that procedural memories represent one type of LTM. But they argue that episodic and semantic are stored in one store and it’s called ‘declarative memory’ (memories that can be recalled consciously). In contrast to procedural memory which is non-declarative.
3) Belleville et al (2006) demonstrated that episodic memory could be improved in older people who had mild cognitive impairment. The participants performed better on a test of episodic memory after training than a control group.
Distinguishing the types of LTM enables us to create a specific treatment to be developed.
4) Synder et al (2014) tested experienced typists for procedural memory. The letters on the keyboard were blanked out but the typists were still able to type without impairment. However, when asked to label the blanked keys, they could only do it with 57% of accuracy. This shows that there are different types of LTM stores and shows although there is an absent of semantic memory, procedural and episodic are still intact.
The Working Memory Model; proposed by Baddeley and Hitch (1974)
WMM is a representation of STM and proposes a multi-component, versatile system.
The Central Executive co-ordinates the activities of the three subsystems in memory. It allocates processing resources to those activities.
Has a very limited processing capacity.
1) Phonological Loop deals with auditory information and preserves the order in which the information arrives. It’s subdivided into
- The Phonological store; stores the words you hear
- The Articulatory Process; allows maintenance rehearsal. The capacity is believed to be 2 seconds worth of what you hear.
2) Visuo-Spatial Sketchpad stores visual and spatial information when required. It also has a limited capacity, which according to Baddeley in 2003 is about three or four objects.
Logie (1995) subdivided the VSS into
-The Visual Cache; store visual data
-The Inner Scribe; records the arrangement of objects in the visual field.
3) Episodic Buffer brings the material together from the other slave systems into a single memory rather than separate strands. It provides a bridge between working memory and LTM.
Evaluation
1) A weakness is that we know very little about the central executive – which is the most important component of the model. It is said to have a limited capacity, however, no one has yet been able to quantify it experimentally. In 1984, Richardson argued that there were problems in specifying the precise functioning of the central executive and he believed that the terminology used in the results of Baddley and Hitch’s model was too vague to be used to explain any kind of result.
2) Dual task performance supports the separation in the VSS.
Baddeley et al 1975 found that participants had difficulty doing 2 visual tasks at the same time, compared to doing one visual and one verbal task at the same time. They did worse in the former because both tasks had to compete for the same system. However, they did the latter with ease because there was no competition due to the tasks using different stores. This means that there must be separate slave system that processes visual input.
3) Shallice and Warrington (1970) studied a patient called KF who suffered from amnesia. They found that his STM for digits was very poor when they read them aloud to him. However, his recall was much better when he was able to read the digits himself. This supports the model because it shows that there are separate STM components for visual and verbal information.
4) Park et al (1999) reviewed a number of studies and concluded that problems with working memory were a key distinction between normal individuals and those with Schizophrenia (sufferers have impaired visual and auditory memory stores). The distinction of the memory stores helps individuals with the diagnosis of Schizophrenia.
5) Braver et al (1997) gave participants tasks that involved the central executive while having a brain scan. Researchers found greater activity in the left prefrontal cortex, as the task increased, so did the activity in the area. This supports the model because the CE allocates processing resources to the slave systems, the harder the task the greater the demand the CE is in.
Explanations for Forgetting: Interference Theory
is an explanation for forgetting (LTM) due to one memory blocking another causing one or both memories to be distorted or forgotten.
1) Proactive is where old information prevents the recall of more recent information. Old memories disrupt new ones.
2) Retroactive is where new information prevents the recall of previously learned information.
These are thought more likely to occur when the memories are similar.
McGeoch and McDonald (1931) studied retroactive interference.
-They changed the similarity between two sets of words. Participants had to learn a list of words until they could recall them with 100% accuracy. They then learned a new list. They were 6 conditions. (independent groups)
Rate of recall on average (mean)
1) Synonyms - 1.2
2) Antonyms - 1.9
3) Words unrelated to the original words - 2.1
4) Nonsense syllables - 2.5
5) Three-digit numbers - 3.7
6) No new list, they just rested - 5.5
Findings: the synonyms group produced the worst recall which supports the idea that interference is strongest when the memories are similar.
Weakness: Lacks mundane realism, the task was very trivial therefore findings cannot be generalised to real life because it is not an everyday task people would face. The study lacks ecological validity.
Weakness: Lab study, control over all variables, cannot generalise findings to everyday life because variables would not occur the same way as it does in real life. Further decreasing the ecological validity.
Strength supports the theory that similar material produces higher interference rates.
Evaluation
1) Underwood (1957) reviewed studies in forgetting. He found that 80% of what is learnt is forgotten within one day. This research supports the proactive interference concept which increases the internal validity of the theory.
2) Baddeley and Hitch (1977) asked rugby players to recall the names of the teams they had played so far in that season, week by week. Most players had missed games so their last team they played might have been two weeks back. The results showed that accurate recall did not depend on how long ago the matches took place but the number of games they played in the meantime. So a player’s recall of a team from three weeks ago was better if they had played no matches since then. This study supports the concept of retroactive interference.
3) Thousands of lab studies have been carried out into explanations of forgetting. This is a strength because these experiments control the effects of irrelevant influences and thus giving us the confidence that interference is a valid explanation for at least some forgetting. This means these experiments are carried out in an objective manner.
4) There is a greater chance that interference will be demonstrated in the lab rather than real life situations. This is because the stimulus and materials used in most of these studies are a list of words. The task of learning syllables or trigrams are not realistic therefore lacking ecological validity, not being able to apply to everyday situations.
Explanations for Forgetting: Retrieval Failure
RF is where we don’t have necessary cues to access memory. The memory is not accessible until a suitable cue is provided. A cue is a trigger of information that allows us to access a memory.
Encoding Specificity Principle; purposed by Tulving in 1983 states that if contextual and state-dependent cues are absent then the information is most likely to be forgotten.
Context Dependent Forgetting are external cues in the environment that will trigger information to be accessible.
State-dependent forgetting is internal cues that will trigger information to be accessible (for example, emotions)
Evaluation
1) Carter and Cassaday (1998) gave anti-histamine drugs to their participants which had a mild sedative effect, making people drowsy which contrasts to a normal physiological state of alertness and awareness.
There were four conditions in which they all took part in (repeated measures)
1) Learn on drug, recall on drug
2) Learn on drug, recall when not on drug
3) Learn when not on drug, recall when not on drug
4) Learn when not on drug, recall on drug
Findings: In the mismatch conditions, recall was significantly worse
2) Godden & Baddeley (1975) conducted a study on 18 sea divers in which there were four conditions they all went through. (repeated measures)
1) Learn on land, recall on land.
2) Learn on land, recall underwater
3) Learn underwater, recall underwater
4) Learn underwater, recall on land
Findings:
- Recall was 40% lower in the non-matching conditions
- Learn on land, recall on land was 13.5 recall rate
- Learn on land, recall underwater was 8.6 recall rate
Weakness: Small sample, cannot generalise findings, lacks population validity
Strength: Divers were in a natural environment there has good ecological validity
3) Studies conducted into retrieval failure is useful for police collecting information because witnesses could improve recall if taken to the same environment.
4) Baddeley (1997) argued that context effects are actually not very strong, especially in real life. Different contexts have to be very different before a real effect occurs. For example, learning something in one room and recalling it in another is unlikely to result in much forgetting because these environments are generally not different enough. This is a limitation because it means that the real life applications of retrieval failure due to contextual cues don’t actually explain much forgetting.
5) Godden and Baddeley (1980) replicated their underwater experiment but used a recognition test instead of recall. Participants had to say if they recognised a word read out to them from the list. When recognition was tested there was no context-dependent effect; the performance was the same in all 4 conditions. This is a further limitation because is means that the presence or absence of cues only affects memory when you test it in a certain way.
Factors Affecting Eyewtiness Testimony:
Misleading Information
MI: Incorrect information that is given to the witness usually after the event. can be leading questions and post-event discussions between co-witnesses and/or other people.
Leading questions are questions in which because of the way it is phrased, suggests a certain answer.
The post-event discussion is where there is more than one witness, they can discuss what they have seen
Evalutation
1) Loftus and Palmer (1974) arranged for students to watch a video of a car accident and answer questions about it. In the critical question, participants were asked to estimate how fast the cars were travelling. There were 5 conditions, each getting a different verb; smashed, collided, bumped, hit and contacted. They found that estimations varied for each verb. For smashed it was 40.5mph but for contacted it was 31.8mph. This shows that leading questions can have an impact on a person’s perception of the question.
> Weakness: The experiment only used students therefore Loftus and Palmer cannot generalise their findings to the whole population due the students of not being representative of the whole population. This therefore lack population validity.
2) Gabbert et al (2003) got participants (60 students from the University of Aberdeen and 60 adults from the local community) to watch a video of the same crime but filmed at different angles. They were then put into pairs in which they discussed the content of the video. They found that 71% of participants mistakenly recalled aspects of the video they didn’t see but picked up in the discussion. (memory conformity)
> Weakness: Participants knew they were taking part in the experiment (didn’t break the informed consent ethical guideline) They were more likely to focus on detail due to not actually witnessing the situation first hand. Therefore, findings cannot reflect real life. Lacks ecological validity
3) Bodner et al (2009) found that the effects of PED can be reduced if participants are warned of the effects. The recall was more accurate for those who were warned that anything they hear from a co-witness is second information and that they should forget it and recall their own memory.
4) Research into misleading information shows that it can have a distorting effect on memory. This has real life applications because police officers need to be careful on how they phrase their questions.
5) Consequences of EWT.
Foster et al 1994 pointed out that what you remember as an eyewitness can have some very important consequences in the real world but it is not the same in studies.
Why leading questions affect EWT
- Response Bias Explanation: the wording of the question has a real no effect on the participant’s memory. It just influences how they decide to answer. When a student heard the verb ‘smashed’ it encouraged them to estimate a higher speed.
- Substitution Explanation: the wording of a question actually changes the student’s memory of the clip. In the second experiment, when students heard ‘smashed’ they were more likely to report seeing broken glass than those who heard ‘hit’. The critical verb altered their memory of the incident.
Factors Affecting EWT: Anxiety
Anxiety is a state of emotional and physical arousal. These include having worried thoughts, increased heart beat and sweatiness.
> Anxiety having a negative effect on recall - weapon focus
Anxiety causes physiological arousal in the body which prevents us paying attention to important cues.
> Anxiety having a positive recall effect
The flight or fight response is triggered which increases alertness and improves our memory because we become more aware of cues
Evalutation
1) Johnson & Scott (1976) invited participants to a lab where they were told to wait in the reception area
There were exposed to 2 conditions:
> The low-anxiety condition in which participants overheard an argument in the following room about equipment failure. After, the target walked passed the participant holding a pen with his hands covered in grease.
> The high anxiety condition in which participants overheard an argument and the sound of glass breaking. This was followed by the target running in the reception area holding a blood-covered paper knife.
Participants then picked out the man from a set of 50 photos. Recall rate for the low anxiety condition was 49% and for the high anxiety was 33%
Weakness: Could lack ecological validity
Although participants were waiting outside the lab, they may have anticipated that something was going to happen which could have affected the accuracy of their judgements.
2) Pickel 1998 conducted a study using hairdresser scissors and a wallet (low anxiety) and a raw piece of chicken and a handgun (high anxiety). The recall was significantly poorer in the high, unusual anxiety condition. This suggests that the weapon focus effect is due to the unusualness rather than anxiety or threat
3) Yuille and Cutshall (1986) conducted a study of a real life shooting in a gun shop in Vancouver. 13 out of 21 witnesses agreed to partake.the interview occurred 4 to 5 months after the incident. these interviews were compared to the original police interviews. the witnesses were asked to rate how stressed they felt at the time of the accident, using a 7 point scale.
- those who reported being very stressed had 88% of accuracy
- those who reported low levels of stress had 75% accuracy
weakness: small sample, can’t be generalised, lacks population validity
4) Parker et al (2006) interviewed people who had been affected by the destruction wrought by Hurrican Andrew in 1992. They found that there was a link between the level of recall and the amount of anxiety/damaged they experienced.
Strength: they used a moderately anxious group which was used to test the inverted-u-theory. Also, supports the concept of the positive effect of recall.
5) Ethical issues: PFH
Improving Accuracy of EWT; Cognitive Interview
A method of interviewing eyewitnesses to help them retrieve more accurate memories. Proposed by Fisher and Geiselman (1992)
There are four main techniques, all based on well-established psychological knowledge of human memory
- Report Everything
> witnesses are encouraged to mention every bit of detail even if they think it’s not relevant - Reinstate the context
> the witness should return to the original scene in their mind and imagine the environment. (related to context-dependent forgetting) - Reverse the order
> events should be recalled in a different chronological order to the original sequence. This prevents people reporting their expectations of how the events must have happened. It’s harder for people to lie if they have to reverse. - Change the Perspective
> witnesses should recall the incident from another person’s perspective. This is done to disrupt the expectations and schemas on recall.
Enhanced Cognitive Interview
> Fisher et al (1987) developed additional elements of the CI to focus on the dynamics of the interaction. Includes how to reduce eyewitness anxiety, minimising distractions and asking open-ended questions.
Evaluation
- Fisher et al 1990
> they trained real detectives to use enhanced cognitive interview with real crime witnesses
> they found that ECI considerably increased the amount of information recalled compared to the standard interview
Strength: the use of real police officers and crime witnesses increased the validity, so it lacks artificial factors - Milne and Bull 2002
> tested each of the cognitive interview techniques singularly or in combination
> all four techniques used singularly produced more information than the standard interview
> however, context reinstatement and report everything were the most effective combination
> this confirmed beliefs of the UK police that some techniques are more effective than others. - Cognitive Interview is time-consuming
> police may be reluctant to try CI because it takes so much time than the standard interview
> the CI also requires special training and not many forces have been able to provide more than a few hours for this
> this means it’s unlikely that the proper versions of the CI are actually used, which may explain why police have not been impressed by it - Geiselman et al (1985) compared standard interview with their cognitive interview on 51 volunteers from a wide demographic background. Participants watched two videos of violent crimes and 48 hours later they were interviewed by using either technique.
The recall rate of those in the standard interview was 35.58 whereas the recall rate for the cognitive interview was 41.67.
Strength: sample, good, wide demographic, can be generalised, good population validity
Weakness: volunteer sample, could be biased, sample could mainly consist of those who are interested in the topic
Research on Duration - STM
Peterson & Peterson 1959
Duration is the length of time information can be held in a memory store
> 24 undergraduates took part in 8 trials in which they were given trigrams and a 3 digit number
they were then asked to count backwards from the 3 digit number to prevent mental rehearsal
on each trial they were asked to stop counting backwards after a various amount of times
3, 6, 9, 12, 15, 18 (these are the retention interval)
Findings
> as the retention interval increased, the number of correct responses decreased. These findings show that STM can only hold information for a very short time
Evaluation
> Artificial stimulus, findings cannot be generalised due to the material not being personal to the participants. lack of ecological validity
Research on Duration - LTM
Bahrick et al 1975
> 392 participants aged between 17 - 74 from Ohio
Recall was tested in two ways
1. Photo-recognition; 50 photos were shown and only some of them went to the high school of the participants
2. Free-recall: they recalled all the names of the graduating class
Findings > Photo recognition accuracy 15 years: 90% 48 years: 70% >Free recall accuracy 15 years; 60% 48 years: 30%
Evaluation
> Field Experiment: high ecological validity
> Confounding variables could have occurred. For example, participants could have seen class mates over the years therefore lack of control
Research on Coding (STM & LTM)
Coding is the format in which information is stored in the various memory stored
Baddeley 1966
> gave different lists of words to 4 groups
1) Acoustically similar 2) Acoustically dissimilar
3) Semantically similar 4) Semantically dissimilar
Participants were shown the original words and were asked to recall
Findings
> Recall immediately (STM recall) they tended to do worse with acoustically similar words
> Recall after 20 minutes (LTM recall) they tended to do worse with semantically similar words
These findings suggest that information is coded semantically in the LTM and STM is coded acoustically, however, if the material sounds similar we get confused.
Evaluation
>artificial stimuli didn’t use a meaningful material, therefore, having any personal value. cannot generalise findings to real life. lacks ecological validity
Research on Capacity in STM
Capacity is the amount of information that can be held in a memory store
Jacobs (1887) developed a technique to measure digit span
> participants aged between 8 to 19 read a list of numbers or letters that they had to recall
> Jacobs increased the list until they could no longer recall accurately
Findings
> on average, they called 9 numbers and 7 letters.
> recall seemed to increase as the age of participants increased. 8 year old could recall 7 numbers and 19 year olds could recall 9 numbers
Evaluation
> Miller 1965 supports the findings
Miller made observations on everyday practice. He noted things came in sevens. E.g 7 notes on the musical scale, 7 days of the week
Therefore Jacob’s study has good concurrent validity
> Lacks temporal validity. it was conducted a very long time ago and early research into Psychology often lacked adequate control. E.g. Confounding variables, participants being distracted thus hindering their performance.
