Memory Flashcards
What is memory and what are the three processes in it?
Memory is the process of retaining learned info and accessing it when needed
Processes:
1. Coding - way info is changed so it can be stored in memory
2. Storage - keeping info within memory system until it is needed
3. Retrieval - recovering information stored in the memory system when it is required
What are the three memory stores?
Sensory register - contains unprocessed info received from senses (has separate stores, iconic store for visual and echoic store for auditory info)
STM- temporary store of info received from SR
LTM - permanent store holding limitless amount of info for a long time
What is capacity and duration?
Capacity - amount info that can be held in memory before new info displaces it
Duration - amount of time info held in memory store before it’s lost due to decay
How did Baddeley investigate coding in STM and LTM and evaluate the study?
STM - Baddeley (1966) gave pps 4 list of words to recall. A had similar sounding words, B had dissimilar sounding words, C had words with similar meanings and D didn’t. He argued STM is coded acoustically (how it sounds) as when tested pps performed worst with A than B, with no difference between C and D
LTM - repeated the experiment and tested pps recall after 20 mins to ensure info passed into LTM. Recall of C worse than D with no difference between A and B. Suggests LTM coded semantically (meaning)
Lab experiment so easy to replicate since controlled variables+ high reliability but has low ecological validity (words recalled artificial and would never happened IRL)
Study investigating capacity of STM (Jacobs)
Jacobs (1887) used digit span test, giving pps diff sequences of digits and letters and asked them to repeat each one straight after he gave it
Sequences got longer by one each time and he found span of STM is 7+-2 pieces of info. More than that means info is displaced. STM capacity increases with age
Study was a long time ago so validity has to be questioned
What is the capacity of SR and LTM
Unlimited
Duration of SR
250 milliseconds
Study investigating STM duration (Peterson and Peterson)
1959 Peterson x2 used nonsense trigrams (random 3 consonants) to test duration
- prevent pps from keeping info in stm using maintenance rehearsal pps were asked to count backwards from 100 in 3s
- after 3 seconds recall 90% accuracy
- after 9 seconds 20% accuracy
- after 18 seconds 2% accuracy
STM lasts 18-30 secs before decay happens
Good study as extraneous variables removed and there was a high level of control, standardised procedures used
Study of LTMs duration (bahrick)
Bahrick (1979) tested 400 pps of various ages on memory of classmates by showing them 50 people and asking if they were classmates or not
90% accuracy within 15 yrs
48 yrs 70% accuracy
Asked to recall names of classmates asw
Within 15 yrs 60% accurate, 30% after 48 yrs
LTM lasts a lifetime but have retrieval failure and need retrieval cues
High ecological validity but hard to control extraneous variables like keeping in touch
What is the multi-store model of memory
The multi-store model of memory (MSM) was developed by Atkinson and Shiffrin (1968). It attempts to explain how information flows from one memory store to another. There are three permanent structures in the memory system: the sensory register (SR), short-term memory (STM) and long-term memory (LTM)
How does MSM explain SR
Environmental stimuli received through sense enters SR, which has an iconic store for visual info and echoic store for auditory info
Fraction of info from SR is attended to and selected for further processing in STM, otherwise info is lost to decay
How does MSM explain STM
If information in the SR is attended to it is acoustically coded into STM, so similar sounding material can be confused. STM is a temporary store for information received from the SR before it is transferred to LTM.
Info can be kept in STM using maintenance rehearsal known as a rehearsal loop. If there’s sufficient rehearsal or elaborative rehearsal (info organised in certain way) then info transferred to LTM
How does MSM explain LTM
If information is sufficiently rehearsed in STM then it is semantically coded into LTM. This is a permanent store holding vast amounts of information for long periods of time.
When information in LTM is needed it is retrieved by STM and then recalled. Sometimes we cannot access information from LTM because of retrieval failure and so we may need retrieval cues to help us access it.
Evaluation of MSM
PROS:
- NEUROBIOLOGICAL EVIDENCE. Scoville 1957 tried to treat HM’s epilepsy by removing areas of brain (hippocampus). Patient couldn’t code new LTM but STM was unaffected suggesting that they’re two separate things
Shallice and Warrington 1970 investigated patient KF who suffered motorbike accident and had reduced STM capacity of 1-2 digits yet LTM unaffected suggesting their two separate stores
- LAB experiments by Murdock 1962 where pps recalled words at beginning and end better than those in middle (serial position effect) support idea of separate STM and LTM
CONS:
Patient KF had poor STM for verbal tasks but not visual tasks suggesting STM has different types which MSM doesn’t show. Also, LTM was unaffected with KF but LTM is retrieved by STM in MSM so it also should be affected if the STM was damaged
The MSM is over simplified in assuming that there is only one type of STM and one type of LTM. Research studies indicate that there are several types of STM, such as one for verbal information (phonological loop) and another for non-verbal information (visuo-spatial sketchpad). Research also suggests that there are several types of LTM, we have episodic memory for life events, semantic memory for knowledge and facts and procedural memory for motor skills.
Baddeley and Hitch (1974) claimed that the MSM could not explain the ability to multi-task; if there is only one type of STM then multi-tasking would not be possible.
What is the working memory model
Baddeley and Hitch (1974) questioned the idea promoted by the multi-store model (MSM) of memory that people only have one type of short-term memory (STM). They also argued that STM is far more complex than simply being a temporary store for information
They instead saw STM as an active store holding several pieces of information while they are being worked on. They argued that LTM is the passive store that only holds previously learned material to be used by STM when needed.
What is the central executive
The central executive drives the whole working memory system and allocates data to the other components, known as slave systems. It also deals with cognitive tasks such as decision making, reasoning and problem solving.
Individuals have a limited attentional capacity, tasks that are automated make less attentional demands on the central executive and so leave us free to perform other tasks. This explains why we can multitask
What is the phonological loop
The phonological loop is the component of working memory that deals with
spoken and written material. It has two sub-components.
- Phonological store (inner ear) is linked to speech perception and holds info in speech form for 1-2 secs
- Articulately loop (inner voice) linked to speech production and used to reverse and store verbal info from phonological store, allowing for maintenance rehearsal
What is the visuo-spatial sketchpad
The visuo-spatial sketchpad stores and processes information in a visual or spatial form. It is used for navigation. Has two components:
- The visual cache stores visual material about form and colour.
- The inner scribe handles spatial relationships.
What is the episodic buffer
Limited capacity store, integrating info from CE, phonolical loop, and VSS, aswell as LTM. It was added by Baddeley in 2000 after he realised the WMM needed a general storage component as slave systems only deal with processing info, and the CE has no storage capacity
Evaluation of the WMM
PROS:
- Neurobiological evidence. Shallice and Warrington (1970) investigated patient KF who had poor STM with verbally presented words but not visually presented words after his motorbike accident. Suggests there’s more than 1 type of STM, one for verbal tasks (phonological loop) and one for visual (VSS)
- LAB experiments. Baddeley and Hitch (1974) gave pps dual task , reasoning task that used CE and reading aloud task that used phonological loop. Pps did both at same time, showing separate components of STM.
- Baddeley et al 1975 gave pps lists of words either short or long and were asked to recall them. Pps recalled more short words than long (word length effect), disproving MSM which suggests that we have a capacity 7+- items
- WMM has practical applications helped those with dyslexia as its improved understanding of how ppls learn to read
CON:
- WMM criticised as psychologists thing CE is vague and untestable. Damasio (1985) presented the case of EVR who had a cerebral tumour removed. He had good reasoning skills, which suggested his central executive was intact, but he could not make decisions, which suggests his central executive was damaged. Indicated CE is more complex than WMM suggests
What are 3 types of LTM
Episodic, semantic, procedural
What is episodic memory?
Memory of key events in life like first day of school, birthdays etc. Has 3 elements (specific details of event, context of events and emotions felt at the time). Stored in hippocampus
What is semantic memory
Memory for facts and general knowledge like maths and remembering capitals. Semantic memories begin as episodic memories because we acquire knowledge based on personal experiences. There is a gradual transition from episodic memory to semantic memory when memory slowly loses its association to particular events and is generalised. Stored in temporal lobe
What is procedural memory
Muscle memory, motor skills and actions like knowing how to drive and tie shoelaces. Procedural memories are typically acquired through practise and repetition and seem to be more resistant to forgetting or amnesia than other types of LTM. We are less aware of procedural memories because they have become automatic, allowing us to focus on other tasks and multitask. Stored in cerebellum
Evaluation of LTM and the types
PROS:
- Evidence for the distinction between episodic/semantic and procedural memory has come from research on patients with amnesia. Typically patients with amnesia are unable to store new episodic or semantic memories but their procedural memory appears to be largely unaffected.
- Scientific evidence captured from brain scans supports the view that there are different types of LTM. For example, when asking participants to recall different types of information, different areas of the brain are shown to be active on an fMRI. Episodic - hippocampus, semantic - temporal lobe, procedural - cerebellum
- Case studies of brain damaged patients offer support for the different types of LTM. For example, Clive Wearing is a man who suffered from a viral infection which damaged his hippocampus. He has no episodic memory and cannot form new semantic memories. However, his procedural memory is intact (e.g. he can still play the piano).
CONS:
- Research into the different types of LTM have typically been conducted on individual patients (e.g. Clive Wearing and HM). Case studies are highly detailed and provide a lot of information but are isolated cases of one individual. It would be inappropriate to assume that everyone’s’ LTM is formed in the same way. The findings cannot be generalised to the wider population.
What is forgetting
a person’s loss of ability to recall or recognise something that they have previously learned
What is the interference theory
Interference theory claims that forgetting occurs when two lots of information become confused in memory. Interference is more likely to occur when the two lots of information are similar to one another. Inference is less likely to occur when there is a gap between the instances of learning.
Retroactive interference is when new learning affects the recall of old information.
Proactive interference is when old learning affects the recall of new information.
Evaluation of interference theory
PROS:
- RESEARCH SUPPORTING PROACTIVE INTERFERENCE. Keppel and Underwood 1962 gave pps 3 letter consonant trigrams at diff intervals, asked pps to count back from 3 b4 recall. Pps remembered first trigrams, researchers concluded memory for earlier trigrams interfered with later ones
- RESEARCH EVIDENCE SUPPORTING RETROACTIVE INTERFERENCE. McGeoch and Mcodonald 1931 gave pps lists of words they had to learn until recalled with 100% accuracy. They then learnt a new lists that was either synonyms or antonyms. Pps asked to remember original list. Pps given list of synonyms had worst recall, showing similar meaning words cause retroactive interference
- This theory has practical applications. Students should be made aware of this theory so that they do not attempt to revise similar content/subjects at the same time, as this will make interference more likely to occur.
CONS
- When interference occurs the loss of information may only be temporary, therefore interference is not a true explanation for forgetting because the information is not actually over-written and is still in Long-Term Memory
- Some psychologists argue that retrieval failure is a much better explanation of forgetting in everyday life than interference. This theory states that we forget when there are not enough retrieval cues to help us remember. Godden and Baddeley (1975) got divers to learn and recall word lists on either dry land or underwater. Results showed that words learnt and recalled in the same context were better remembered as there were retrieval cues in the environment to help them remember the words.
What is the retrieval failure theory
Retrieval failure argues that forgetting occurs in the absence of appropriate retrieval cues. When information is initially placed in memory, data associated with this information is stored at the same time. If these retrieval cues are not available at the time of recall, it may make it appear as if you have forgotten the information when in fact you just cannot access it at that time.
Some retrieval cues are linked to the material that needs to be remembered in a meaningful way, for example, the anagram ‘STM’ may lead people to recall all sorts of information about short-term memory. Other retrieval cues are coded at the same time of learning but not in a meaningful way.
What are context and state cues
Context:
The environment in which material is learnt can act as a retrieval cues. This means that if you recall information in the same environment that you learned it (e.g. the same classroom) then your recall will be better.
State:
An individual’s physical state (e.g. mood) can affect their recall. Research studies suggest that recall is facilitated if people have a similar physical state at recall as when the information was coded. If you are not in the same physical state at recall as you were when you learned the information then you might fail to access the information.
Evaluation of retrieval failure theory
PROS:
- Abernethy (1940) demonstrated the importance of context-dependent cues. They tested participants’ recall using a mixture of familiar and unfamiliar instructors and teaching rooms. Participants tested by a familiar instructor, in a familiar room, performed the best because the instructor and room acted as retrieval cues.
- Godden and Baddeley (1975) also demonstrated the importance of context- dependent cues. They asked divers to learn and recall word lists on either dry land or underwater. Results showed that words learnt and recalled in the same context were better remembered as there were retrieval cues to help them remember the words.
-Darley et al. (1973) showed the importance of state-dependent cues. They found that participants who hid money in a large warehouse while under the influence of cannabis were more likely to recall the hiding place when in a similar drugged state.
- Retrieval Failure has practical applications. Whenever possible students should learn/revise in the room, in which they will take their final exams.
CONS:
- Baddeley (1997) argues that the influence of retrieval cues is not actually very strong. In real life, we often recall something in a different context to where we learnt it. For instance, students do not often take their GCSE examinations in the classroom where they learned the information they need for that exam.
What are leading qs
Leading questions are questions that are phrased in such a way as to encourage a witness to give a certain answer
Diff between response-bias and substitution-bias
The response-bias explanation argues that leading questions do not affect memory, merely the answer a person chooses to give. However, the substitution-bias explanation proposes that leading questions distort memories because they contain misleading information.
Evaluation of leading qs
PROS:
- Loftus and Palmer (1974) showed 45 American students a film of a car crash and then asked them to estimate the speed that the cars were travelling when they crashed. However different verbs were used in the question depending on the condition. The verbs were contacted, hit, bumped, collided, or smashed. Pps in contacted estimated 31mph but with smashed estimated 41 mph. A week l8er pps asked if the saw broken glass even tho there wasn’t, 32% of pps in smashed said yh compared to 12% in controlled condition showing leading qs have an impact on what ppl recall as it can change entire memory of life event
- ^^^^ study was lab and highly controlled, no extraneous variables, increasing validity replicability and reliability
CONS:
- Low ecological validity (video of car crash is different to people who actually witness one as they have stronger emotional connection to event) and low population validity (45 American students who less experienced drivers and worse at estimating speed so can’t generalise to other populations. Experienced drivers wouldn’t be susceptible to leading qs)
Evaluation of post event discussion
Pros:
- study has high population validity as there were two different populations and students + adults were used and there wasn’t a significant difference between what the young and old showed
CONS:
- This study lacks ecological validity. The participants knew they were taking part in an experiment and they therefore are more likely to have paid close attention to the details of the video clip. The results do not reflect real life where witnesses may be exposed to less information.
Loftus study on anxiety
Loftus (1979) wanted to see whether anxiety affected a person’s ability to recognise the perpetrator of a crime. In the experimental condition Loftus arranged for participants to overhear a heated and hostile argument between two people. They also heard the sounds of furniture being overturned and broken glass. Then a man emerged carrying a letter opener covered in blood. In the control condition participants overheard a conversation between two people about laboratory equipment failure before a man with grease all over his hands emerged carrying a pen. Participants were then asked to identify the person they had just seen from 50 photos.
FINDINGS
Only 33% of the participants in the bloody letter opener condition recognised the photo of the person carrying the letter opener whereas 49% of the participants in the pen condition recognised the photo of the person carrying the pen. Loftus (1979) argued that this occurred because people in the former condition had focused on the bloody letter opener rather than the person carrying it, because the letter opener was a weapon that could pose a threat to them.
EVALUATION OF ANXIETY
PROS:
- This study is supported by other research studies. Loftus & Burns (1982) allocated participants into one of two conditions. One group watched a violent short film where a boy was shot in the head. The other group watched a non-
violent short film of a crime. Participants were less accurate in recall when they saw the short film with a gun than those who watched the non-violent movie.
CONS:
- low ecological validity (anticipated something would happen, affects accuracy of judgements and validity of study)
- violated numerous ethical guidelines, deceived about nature of experiments and not protected from psychological harm (they actually thought the guy killed someone which could’ve caused extreme distress)
- Yuille and Cutshall (1986) investigated the effect of anxiety in a real life shooting, in which one person was killed and another person seriously wounded. 21 witnesses were originally interviewed by investigating police and 13 of these witnesses, aged between 15 and 32, agreed to take part in Yuille and Cutshall’s follow-up interview five months later. The witnesses were accurate in their eyewitness accounts five months later and little change was found in their testimony. Furthermore, the witnesses avoided leading questions and those who had been most distressed at the time of the shooting gave the most accurate account. In real life cases leading questions and anxiety do not affect the accuracy of eyewitness testimony the same way they do in the laboratory.
- There are individual differences in how anxiety affects memory. Some people actually have better recall when they are anxious. Christianson and Hubinette (1983) conducted a research study using 110 real life eyewitnesses who had witnessed one of 22 bank robberies. Some were onlookers and some were bank clerks who had been directly threatened by the robbers. It was found that victims were more accurate than onlookers in their description of the bank robbers.
What is anxiety and how does it affect EWT
Anxiety is a state of apprehension, uncertainty, and fear resulting from a threatening situation. When anxiety is high it can often impair both physical and psychological functioning. Several psychologists have suggested that the anxiety that occurs when witnessing a crime can prevent accurate and detailed recall of that crime. The presence of a weapon during a crime increases anxiety and therefore could impair witnesses’ memory of the crime. People focus more on weapon due to anxiety and threat it causes, leading to lesson information about criminal themselves being recalled (weapon focus effect)
Cognitive interview main parts
Geiselman et al. (1985) developed the cognitive interview to improve police interview techniques and obtain more accurate information from eyewitnesses. It consists of four main stages.
- Context Reinstatement = The witness tries to mentally recreate an image of the situation, including details of the environment, such as the weather conditions and their emotional state, including their feelings at the time of the incident. These may act as retrieval cues (context-dependent cues) to improve recall.
- Report Everything = The interviewer encourages the witness to recall all details about the event, even though these details may seem to be unimportant. This may highlight details which have been overlooked and trigger other memories.
- Recall From Changed Perspective = The witness tries to mentally recreate the situation from different points of view. This promotes a more holistic view of the event which might enhance recall.
- Recall in Reverse Order = The witness is asked to recall the scene in a different chronological order. This should verify the accuracy of the witnesses’ account.
More things were added in 1987 by Fisher:
- let witness relax and speak slowly to reduce anxiety
- avoid distractions
- use open-ended qs
- offer comments to clarity
Evaluation of cognitive interview
PROS:
- Geiselman et al. (1985) showed participants a video of a simulated crime and tested recall using the cognitive interview, standard interview or hypnosis. The cognitive interview led to the most information being recalled by the eyewitnesses.
- Fisher et al. (1990) trained real police officers in Miami to use the enhanced cognitive interview when interviewing eyewitnesses. They found that on average there was a 46% increase in the amount of information witnesses gave. 90% of the information that could be verified was accurate.
CONS:
- Koehnken et al. (1999) found that witnesses recalled more incorrect information when interviewed with the cognitive interview compared to the standard interview technique, perhaps because more detailed recall increases the chance of making a mistake
- The cognitive interview is time consuming to implement and police officers often do not have the time, training and resources to use it.
- Memon et al. (1993) reported that police officers believed that Recall From Changed Perspective stage of the cognitive interview misleads witnesses into speculating about the event they witnessed rather than reporting what they actually saw. For this reason the police were reluctant to use it
What is EWT
Eyewitness testimony (EWT) is the evidence supplied to a court by people who have seen a crime, based on their memory of the incident. This evidence can include an identification of the perpetrator or details of the crime (sequence of events, the time of day etc.). Juries are often heavily influenced by eyewitnesses.
post - event discussion
- The memory of an event can be contaminated through discussing events with others due to misinformation (memory contamination). Also, a desire for social
approval can lead co-witnesses to reach a consensus view of what happened (memory conformity). - Gabbert et al. (2003) put participants in pairs and got them to watch a different video of the same event so that they each got unique details. In one condition the pairs were encouraged to discuss the event with one another before individually recalling the event. In the other condition they did not discuss what they had seen with one another. 71% who discussed event mistakenly recalled details they didn’t see themselves but were told by their partner, demonstrating effects of memory contamination
