Memory P1 Flashcards
Coding, capacity and duration def
coding -> changing information so that it can be stored
capacity -> the amount of information that can be held in a memory store
duration -> the length of time information can be held in memory
short term memory, long term memory and sensory register def
STM = a limited capacity memory store
LTM = a permanent memory store
SR = Registers the immediate information coming in from the environment through our sense (can be visual/auditory/tactile)
sensory register (capacity)
SPERLING RESEARCH
- Using a tachistoscope presented a grid of letters for less than 1 second.
- On average, 4 of 12 items remembered.
= Shows that large amounts of info can be taken in but only recalled for a brief amount of time.
+ controlled lab setting
- low ecological validity
sensory register (duration)
=SPERLING RESEARCH
Approx 500ms
sensory register (coding)
CROWDER IDEAS
- The sensory register codes into two different stores…
1) visually -> iconic store
2) auditory -> echoic store
=Dependent on sensory input/stimuli
STM (capacity)
MILLERS THEORY
= Capacity reached at 7 plus or minus 2 items and the amount of information increased by chunking -> organizing info into meaningful chunks.
Supported by……
JACOBS RESEARCH
= Added a digit each time to a sequence of numbers. Ps could recall 9.3 numbers and 7.3 letters accurately.
STM (duration) + eval
PETERSON + PETERSON’S RESEARCH
-Ppts asked to recall trigrams (three consonants eg BHJ)
- Interference tasks (eg counting back from 60) to prevent rehearsal
- After 3sec delay = 80% recalled acc
- After 18sec delay = 10% recalled acc
= STM duration is around 18seconds or less
= Overtime our STM will degrade without active recall
eval:
1) Easier to establish cause and effect/ standardized
= Used distraction tasks to prevent rehearsal. They use the task of counting backwards from a given number in threes. This prevented rehearsal meaning that only recollection of the trigrams wasn’t influenced from active recall. Meaning it was easier to establish cause and effect through the distraction tasks.// standardized procedure meaning the study had both high replicability and reliability as all participants were made sure to have experienced the same process. Therefore, producing valid conclusions as any findings of duration of memory could not have been caused by active recall.
2) artificial stimuli not replicable to real life
STM (coding) + eval
BADDELEY’S RESEARCH
- Presented words acoustically similar (eg cat,hat,mat) or acoustically dissimilar (eg pen, shoe, glass).
- Ps asked to recall immediately.
- Ps recall better for acoustically dissimilar words
= We code STM acoustically, with words that are auditory clear
eval:
1) Lacks ecological validity
= It was a lab experiment in which all participants were asked a series of acoustically similar and dissimilar words in a highly controlled, unrealistic environment. This means that any findings initiator cannot be applied certainly to real life instances of human memory coding as behaviours shown may be different to that in real life. It is unlikely for participants to be asked such tasks in their day-to-day life. Therefore, the study lacks validity as it may not be sufficient evidence for the coding of humans memory as it could be studying unrealistic behavior due to the unrealistic condition.
2) controlled and standardised
LTM (capacity)
WAGENAAR
- Conducted research on himself, creating a diary of 2400 events over 6yrs.
-recall was excellent
= LTM capacity is unlimited
+ stimuli reflect real life memory so has eco validity
- case study so unrepresentative
LTM (duration) = eval
BAHRICK ET AL RESEARCH
- 392 US graduates asked on either
1) photo recognition (matching name to pic)
2) free recall (name person in picture)
Findings:
1)photo rec
after 15 yrs -> 90% recall
after 48 yrs -> 70% recall
2) free recall
after 15 yrs -> 60% recall
after 48 yrs -> 30% recall
= LTM duration is up to years
=Therefore, loss is fast to begin with, then slows down.
eval:
1) High ecological validity
= Study used real life memories that participants record by matching pictures of classmates with their names. Therefore, these results reflect our memory for real life events, so it can be applied to everyday human memory.
2) Lacks population validity
= The sample consisted of 392 American university graduates. Psychologists are unable to generalize the results to other populations as it’s culturally biased. For example, students from the UK may recall their names better/ worse after 48 hours due to their education systems or relationships with classmates etc (if spent a lot of time with them more likely to remember them). Therefore, we are unable to conclude whether other populations would demonstrate the same ability to recall names and faces after 48 years.
Three modalities of coding
visual
auditory
semantic
LTM (coding) + eval
BADDELEY’S RESEARCH
1) semantically similar (huge, tall, big)
2) semantically dissimilar (snow, skirt, pen)
20 mins after dissimilar recalled better
= Therefore, LTM uses semantic (meaning) coding
eval:
1) Real life application
= For instance, they found that the LTM was semantically coded meaning these findings can be used by students to strategize their revision techniques better. This means that if a student is struggling to recall information from a couple of topics ago, they may find it useful to acknowledge the meaning of their work rather than just active recall. Therefore, giving Baddeley’s research value as it can be used universally, benefiting lives.
2) Lacks ecological validity
= It was a lab experiment in which all participants were asked a series of acoustically similar and dissimilar words in a highly controlled, unrealistic environment. This means that any findings initiator cannot be applied certainly to real life instances of human memory coding as behaviours shown may be different to that in real life. It is unlikely for participants to be asked such tasks in their day-to-day life. Therefore, the study lacks validity as it may not be sufficient evidence for the coding of humans memory as it could be studying unrealistic behavior due to the unrealistic condition.
The Multi store model of memory (atkinson and shiffrin)
A representation of how memory works in terms of three stores called the sensory register, short term memory and long term memory. It also describes how information is transferred from one store to another, what makes some memories last and what makes some memories disappear.
Types of forgetting + what store they occur at
SR -> lack of attention
STM ->
Decay : The gradual fading of information that is not paid attention to until it is forgotten.
Displacement: When new information pushes out the old due to ‘full capacity’ in the STM.
LTM->
Decay: The gradual fading of information that is not paid attention to until it is forgotten.
Retrieval failure: Inability to recall information because the cue needed to trigger the memory is not present.
Interference: When information is similar and so it gets confused/muddled.
General eval of MSM
Pro:
1) HM
= underwent surgery to relieve his epilepsy
-> removed hippocampus (crucial for memory) on both hemispheres.
-> LTM for events that happened before his accident were still intact BUT could not create new memories as he was unable to transfer information from his STM to LTM
(meaning he was trapped in a world that lasted as long as his STM)
= memory split into different stores, which likely have different brain locations.
2) Primary recency effect
= A serial position curve shows that when a participant was shown a list of words, the first and last word or remembered better than those in the middle. This is because words at the beginning of the list have been rehearsed into the LTM while those at the end are still currently in the STM. Words from the middle are poorly recalled as they do not have a chance to be rehearsed into LTM or enter STM, as its capacity is full. Therefore, supporting MSM as it shows our memory is split into different stores rather than just one- STM and LTM; And that information will remain in each store based on the capacity, duration and rehearsal of information.
Con:
- Lacks ecological validity
= Lab based setting using artificial tasks (ie PRE /SPC using list of words ) showing it is hard to know whether the processing that occurs to form memories of everyday information can be applied in the same way. Therefore, it is difficult to use findings to offer support for the MSM as an explanation for our memory.
Working Memory Model
= Baddeley and Hitch
- Wanted to replace the short-term memory of the MSM because…
1) STM must be more complex than just a single unitary store that only exist pass information on to LTM.
2) STM must be an active processor holding multiple different types of information simultaneously while being worked on
WMM: a representation of the STM that suggests it is a dynamic processor of different types of information using subunits coordinated by a central decision making system.
- Components differ in terms of capacity and coding
- Not only stores info but it processes it (hence working)
episodic buffer (slave store)
ADDED BY BADDELEY IN 2000
= Acts as a ‘backup’ store, which holds and integrates visual, spatial and verbal information from the VSS, PL, CE and LTM.
- coding : visual + acoustic
- capacity: approx 4 chunks
EXAMPLE:
- someone giving you verbal instructions on a route to Petersfield (uses both acoustic and visual coding)
- watching a film
central executive
- Monitors and coordinates the operation of the other components of the store
- The ‘Boss’ acting as a filter choosing what to ignore and what to pay attention to (does not store info)
-Capacity : very limited (4 items) - Modality free (can code in different formats)
Ie reading a book, sister comes in turns on tv, the central executive will decide whether to continue using the phonological loop or switch to the visusopatial sketchpad to watch what’s on tv
Visuo-spatial sketchpad (slave store)
-processes visual and spatial info
- responsible for setting up and manipulating mental images
- capacity : limited to 3-4 objects (Baddeley’s research)
Logie Research subdivided it into two:
1) visual cache : passive store of form and colour
2) inner scribe : active store holding the relationships between objects in 3D space (records visual arrangement of objects coded in visual field).
EXAMPLE:
- recognizing a friend in the street
Phonological Loop (slave store)
- processes auditory info
- coded: acoustically
= 2 subdivisions…
1) phonological store (inner ear) -> stores words
2) articulatory process (inner voice) -> allows maintenance rehearsal (repeating sounds or words in a loop to keep them under working memory while they are needed). The capacity of this lupus believed to be 2 seconds worth of what you can say.
EXAMPLE:
- working out a sum of 3+2 in your head
Evaluation of WMM (pros) : Baddeley et al
-1) Research evidence to support it
= Baddeley et al (1975) - Dual Task Experiment
Participants we’re given a visual tracking task (tracking a moving light with a pointer) at the same time they were given one of two tasks…
1) To describe or trace ‘F’ (uses visuo-spatial sketchpad)
2) To perform a verbal task (uses phonological loop)
Findings:
= Participants did better on the 2) verbal task as they use two separate slave stores that were not overloaded with information unlike on 1) that uses the Visuo-spatial sketchpad for both information. Thus, because 1) uses both visual tasks which competed for the slave system, it was overwhelmed and ps found it difficult to do both at the same time.
= Therefore, showing support for the WMM that there are different stores in our STM that effect our ability to process information.
Evaluation of WMM (pro) : KF
Shallice + Warrington studied KF (a man whose brain had been injured in a motorcycle accident)
- LTM was normal but STM severely impaired…
A) Only able to recall 1-2 items (rather than 5-9)
B) STM for visual stimuli better than auditory letters/digits
C) normal STM SPAN for MEANINGFUL sounds (eg a doorbell, telephone ring etc) even though his STM span for words, letters and digits was very limited.
- Therefore, suggesting KF had more than one STM store, which is consistent with WMM.
Evaluation of WMM (cons)
1) Lack of clarity over the central executive
= The exact role off the Central Executive, which is thought to be the most important component of the WMM, remains unclear. This is because the complexities of this component such as its role in planning, attention, coordination of tasks, makes it very difficult to investigate empirically - it is a store in our heads. This means that the WMM cannot provide a complete explanation of how STM works as we cannot know for certain that the store even exists. As a result, the theory lacks reliability due to its lack of sufficient evidence.
2) Problems with supporting evidence
= The Dual Task Experiments uses simplistic stimuli. It is unlikely that this procedure of tracing the letter ‘F’ or performing a verbal test, will occur in real life. This means that, due to the artificial task, the findings lack ecological validity and cannot be generalised to all memory processes in everyday life.
= The case study KF may not be reliable because it is a unique case of a patient (case study) who has suffered a traumatic experience and findings are therefore difficult to generalise to others. Thus, findings from both studies cannot be applied for objective support - meaning more research is needed.
Types of LTM
Episodic Memory -> Personal events such as people, places,objects and behaviours.
->Time stamped (can recall when it happened).
-> Explicit memory (requires conscious effort to recall)
-> Declarative (involves verbal recall)
-> Less resistant to forgetting
EG What I ate last night
Semantic Memory -> Knowledge of the world such as concepts, facts and words.
-> NOT time stamped
> Explicit memory
-> Declarative
-> Less resistant to forgetting
EG What the capital of France is
Procedural Memory -> Knowing how
to do something (out motor skills).
-> Easy to do, difficult to explain
-> NOT time stamped
-> Implicit memory ( does not require conscious effort to recall)
-> Non-declarative (does not involve verbal recall)
-> More resistant to forgetting
EG How to ride a bike
Evaluation of the Types of LTM (pros)
PROS:
1) evidence support
= Clive Wearing case study shows that there are different types of LTM. His semantic and procedural memory was intact but his episodic memory was severely damaged (ie forgot family events, when he last saw his wife).
2) real life application ; cog training as a treatment
= If we can distinguish different types of LTM it enables treatments. Belleville et al -> EM improved in older ppl who had mild cognitive impairment that received cog training>those without. Therefore knowledge of this area has green useful and beneficial to society.
Evaluation of the Types of LTM (cons)
CONS:
1) Cohen and Squire
= Division of LTM into 3 is too complex (only need 2). Claimed the episodic and semantic memory was too similar and should acc be split into procedural ( non-declarative) and declarative.
2) evidence based on case studies
= Clive Wearing is a unique individual therefore cannot be generalised to wider population that there are different types of LTM for everyone. Therefore. further research is needed.
Interference Theory (for LTM)
Proactive interference -> when older memories disrupt the recall of new memories. (e.g memory of an old phone number disrupts attempts to recall new one).
Retroactive interference -> when newer memories disrupt the recall of older memories. (e.g memory of a new car registration prevents recall of previous one)
Explanations for forgetting
- interference (retro pro)
- retrieval failure (context and state)
Key research of Interference theory (ao3)
1) McGeoch + McDonald
- studied retroactive interference
- ps had to learn a list of words until 100% accurate
- then, learnt a new list
6 Groups:
1-> synonyms
2 -> antonyms
3 -> unrelated
4 -> nonsense syllables
5 -> 3 digit numbers
6 -> no new list
…then had to recall original list.
= Found that the synonym group produced the worst recall. Therefore, retroactive interference exists!😊
Issue -> low ecological validity/too artificial -> does not replicate real life tasks, does not explain cognitive process
2) Schmidt et al (strength of interference)
- found a positive correlation between number of times a person had moved house outside the same area + the number of street names forgotten
2 types of Retrieval Failure (For LTM)
-> explanation for forgetting
Context-dependent forgetting -> when environmental cues are different, making recall difficult.
State-dependent forgetting -> when your internal environment is different (emotions,drunk vs sober), making recall difficult.
Research into the 2 types of retrieval failure (ao3)
Godden and Baddeley
- context-dependent forgetting
- 18 divers learn a list of 36 unrelated words
4 conditions:
a) learn on beach/recall on beach
b) learn on beach/recall underwater
c) learn underwater/recall underwater
d) learn underwater/recall on beach
=Found more words were recalled when in the same environment for learning and recalling the list. Therefore, context-dependent forgetting is evidenced here.
2) Carter and Cassaday
- state-dependent forgetting
- gave ps anti-histamines (make you drowsy but cure hayfever)
- drowsiness caused a diff internal state
- learn a list of words
4 conditions:
a) learnt on drug/recalled on drug
b) learnt on drug/recalled not on drug
c) learnt not on drug/ recalled on drug
d) learnt not on drug/ recalled not on drug
=Found that mismatch between internal states made recalling the list of words worse. Therefore, state-dependent forgetting is supported here.
Factors affecting accuracy of EWT
leading questions
post-event discussion
anxiety.
Johnson + Scott Study (eyewitness testimony)
=Anxiety having a negative effect on recall
procedure :
- exposed to one of two conditions;
1) low anxiety -> overhead a discussion in a lab about equipment failure, man emerged holding a pen with grease on hands.
2) high anxiety -> overhead a hostile discussion between ppl in a lab, glass smashing , chairs crashing then a man emerged holding a paper knife covered in blood.
Then they were given 50 photos and asked to identify which person emerged from the lab
findings:
-pen -> identified person 49% of the time
-knife -> identified person 33% of the time
-led to the Tunnel Theory/weapon focus -> argues fear/anxiety induced from the sight of a weapon narrows focus and leads to …
a) accurate recall of central ideas (knife)
b) less accurate recall of peripheral details (the man).
Johnson + Scott evaluation
1) Lab based / Field experiment
= Particpants may have been expecting something to occur and therefore displayed demand characteristics.
Findings lacked ecological validity, meaning it was hard to determine how anxiety affects eyewitnesses to recall for real events.
2) May test suprise> anxiety
= People may focus on the weapon, not dude being scared, but because they are surprised.
Pickle’s Study conducted an experiment, using scissors handgun, a Wallet and a raw chicken in a hairdressing video. Eyewitnesses recollection was significantly lower in the unusual conditions (handgun and chicken). Due to surprise!
3) No protection from harm -> forced anxiety when not necessary
Pros:
practical application
can establish cause and effect
Christianson + Hubinette (eyewitness testimony)
= Anxiety having a positive effect on recall
procedure:
- questioned 110 witnesses about real life bank robberies
2 groups:
1) high anxiety group (employees) -> directly threatened
2) low anxiety group (bystanders) -> indirectly involved
findings:
- those directly affected (high anx) = better recall > indirectly affected (low anx)
conc:
- Therefore, people (especially victims) are good at remembering highly stressful events if they occur IRL > artificial settings; suggesting that high-level anxiety enhances recall.
Christianson + Hubinette Evaluations
Pros:
1) high ecological validity
= Real life bank robbery so displays accurate/valid findings as represents real life. Therefore, generalisable to real life.
2) real life application
=Police officers are likely to want eyewitness interviews from cashiers/employees>bystanders due to this research.
Cons:
1) unethical -> no protection from harm (putting them in an uncomfortable recall of traumatic events)
2) individual differences -> participant variables (ie employees may be given training for these situations, so more likely to remain calm and have better recall due to the training, not the anxiety). Therefore, difficult to establish cause and effect.
3) only applicable to bank robberies
Yerkes Dodson Law (due to other 2 studies contradicting each other)
-> use as an eval point
- low levels of anxiety = lower performance on recall
- memory can get significantly better if anxiety rises
- reaches an optimum point, as your more aware
- then, recall begins to decrease as you get overly anxious, as you become too alert and cannot focus properly
Loftus and Palmer (leading questions)
procedure:
Showed video of a car accident and asked one of two following questions…
1) How fast were the cars going when they smashed
2) How fast were the cars going when they contacted.
findings:
The adjective had an effect on speed estimation.
1) ‘smashed’ -> highest estimate 40.8 mph
2) ‘contacted’ -> produced the lowest estimate
3) A week later asked if they had seen any broken glass =Those in the ‘smashed’ group were consistently more likely to answer ‘yes’ (incorrect)
CONCLUSION : People’s memory can be easily influenced by changing a single word in a question, altering their memories of details when asked at a later date.
Loftus and Palmer : leading questions (evaluation)
Pro -> Demonstrates the fallibility of EWT due to leading questions. Therefore, having real life application as they have led to improved police interviewing strategies, whereby police us open questioning to elicit a more accurate recall of an event.
Con -> Lack ecological validity.
= Lab, so artificial environment, increasing demand characteristics. Watched a video of a car accident (low anxiety), p’s may recall better/worse if they had experienced a real accident (due to anxiety).
Gabbert et al (post-event discussion)
procedure:
-matched pairs design
-each person watched the same crime video (but filmed from different points of view)
-both participants then discussed what they had seen before individually completing a recall test
- a control group did not have the opportunity for any post-event discussion
findings:
-71% mistakenly recalled aspects of the event they did not see in the video, but picked up during discussion.
- control group : 0% mistake
CONCLUSION: EW often go along with each other to win social approval or because they believe the other witnesses are right and they are wrong. (memory conformity).
Memory contamination = where the new info from post event discussion has altered or distorted the original memory
Gabbert et al : post-event discussion (evaluation)
Pro-> Controlled
= All watched same video of a crime (standardised)
-> empirically observe the effects of the video on recall accuracy. Provides clear evidence for how post-event discussion can influence eye-witness testimony.
Pro-> Practical application
= As post-event discussion have been shown to contaminate an EW memory, police now ensure EWs do not have the opportunity to discuss what they saw, in order to obtain more accurate testimonies.
Pro->matched pairs design (controlled ev’s) less chance of invidual diff between conditions.
Con - > Lab
= Demand characteristics and so responses given may not reflect the same levels of memory contamination which might be seen in real life events; where the implication of giving ‘inaccurate’ info are greater?
Improving eye witness testimony (Cognitive Interviews: Fisher + Geiselman’s 4 stages )
A method of interviewing eyewitnesses to help them achieve more accurate memories. It uses 4 main techniques…
1) Report everything -> interviewer encourages the reporting of every single detail, even if it seems irrelevant (such detail may trigger other memories).
2) Reinstate the context-> interviewee mentally reinstates the environmental and personal context of the incident, may recall the scene, weather, what you were thinking and feelin (based on retrieval failure -> cues may trigger the recall).
3) Reverse the order-> interviewer tries alternative ways through the timeline of the incident (reduces effect of schema filling in gaps on recall).
4) Change perspective-> interviewee describes event from different viewpoint (prevent effect of schemas on recall)
The enhanced Cognitive Interview (Fisher)
- no distractions
- active listening (from interviewer)
- eye contact
- no interruption
- social interaction
- let witnesses do most of talking
- remain fluidity
- allow them to stop naturally
- make them slow down and focus on feelings
Cognitive interview pros
1) support of effectiveness
= a meta analysis by Kohnken et al combined data from 55 studies comparing cognitive interviews with standard police interviews. Found the cognitive interview gave an average of 41% increase in actual information. Therefore CI are effective on increasing witnesses recall of information.
2) Geiselman (1985)
- Participants viewed a film of a violent crime
-48 hours interviewed by a policeman using one of three methods…
a) the cognitive interview
b) standard interview used by the Los Angeles Police
c) interview using hypnosis.
CI -> 41 AROUND recall accurately
Standard -> 29
Hypnosis -> 38
Conclusion: The cognitive interview leads to better memory of events, with witnesses able to recall more relevant information compared with a traditional interview method.
Cognitive interviews cons
1) Not all elements are useful
= Milne and Bull found that each of the four techniques used alone produce more information than the standard police interview. But they also found that using a combination of report everything and reinstate the context produce better record than any of the elements or combination of them. Confirming police officer suspicions that some aspects of CI are more useful than others. This cast some doubt on the credibility of the overall overall covenant of interview.
2) Time consuming
= More time is needed to establish rapport with a witness and allow them to relax. It so require special training and many forces do not have the resources to provide more than a few hours.
