Outline and evaluate research related to the features of short/long term memory
AO1
• Coding- how you store and retrieve memories
• Capacity- how much information you can store
• Duration- how long you can store the information for
Coding STM • Baddeley- Participants shown lists of words that were acoustically or semantically similar and dissimilar and asked to recall them in order • Information recalled acoustically LTM • Recalled words after 20 minutes • Information recalled semantically
Capacity
STM
• Jacobs- Read out sequences of numbers or letters increasing in length
• Mean span for numbers was 9.3 items, letters was 7.3
• Miller says it is 7 items +/- 2
LTM
• Unlimited
Duration
STM
• Peterson- 24 undergradates given a trigram and a 3-digit number and were asked to count down from the number in intervals for different durations of time, and then recall the trigram
• 18-30 seconds
LTM
• Bahrick- Photo recognition and name recallation (free recall) of high school peers
• 48 years, unlimited
• Baddely +lab experiment, variables controlled so high internal validity
-used artificial stimuli rather than meaningful material, low ecological validity
• Jacobs -conducted a long time ago, may have had confounding variables that weren’t controlled
• Miller -overestimated capacity of STM, Cowan thought it was 4 items
• Peterson -artificial task, low ecological validity
• Bahrick -low control of confounding variables
+high external validity
Describe and evaluate different types of long-term memory
AO1
Semantic Memories of facts and knowledge
Procedural Memory of skills, how to do activities
Episodic Personal memories of events
• Effort- S: A lot, deliberate effort, P: None, E: Quick, but conscious effort
• Time stamping - S: no, P: no, E: yes
AO3
• + Tulving et al, asked memory questions to people in MRI scanners, observed semantic used frontal love, procedural used cerebellum, and episodic used the temporal lobe and frontal lobe. As they happen in different parts of the brain, they can’t be the same
• + Clive Wearing, lost episodic memory due to a viral infection, but has procedural and semantic, only remembers his wife, must be different types of LTM as only one was damaged
• + HM had his hippocampus removed due to epilepsy, limited his episodic memory but still had procedural and semantic, must be different types of LTM as only one was damaged
• - Clive Wearing and HM aren’t useful as evidence as they both had brain damage so we don’t know exactly which parts of the brain were affected, so the damage may not have been the exact cause of the memory loss, so you can’t conclude a causal relationship between brain region and type of LTM
• - Generalisability- case studies of few people, lacks population validity
Discuss the multi-store model of memory
AO1
• Liner model with unitary states
Input—Sensory store—Pay attention—Short term store—Prolonged rehearsal—Long term store (maintenance loop goes back from long term store to short term store)
• Sensory store- coding is visual (iconic memory) or acoustic (echoic memory), capacity is very large, duration is less than a second
• STM store- coding is acoustic, capacity is 7 +/- 2 chunks of information, duration is 18-30 seconds
• LTM store- coding is semantic, capacity is unlimited, duration is unlimited
AO3
• - Watkins and Craik believed it is elaborate rehearsal which allows information to be stored in LTM, not maintenance rehearsal
• - Doesn’t include 3 types of LTM (use an LTM study as evidence)
• + Baddeley, coding shows a difference in STM and LTM, good that it has separate STM and LTM store
• + Miller, capacity shows a difference in STM and LTM, good that it has separate STM and LTM store
• - Working memory model is better (use KF case study)
Describe and evaluate the working memory model
AO1
Central executive, branches out to phonological loop, visuo-spatial sketchpad and episodic buffer, all go to long term memory
• Central executive- monitors incoming data, makes decisions and allocates slave systems to tasks, limited storage capacity
• Phonological loop- deals with auditory information and preserves order it arrives in, phonological store stores words you hear, articulatory control system allows maintenance rehearsal and is acoustically coded
• Visuo-spatial sketchpad- processes visual and spatial information, capacity is 3-4 pieces of information
• Episodic buffer- merges visual and auditory information, capacity of 4 pieces of information
AO3
• + KF suffered brain damage, had poor STM for verbal information but could process visual normally
• - Generalisability- KF is only one person, lacks population validity
• + Baddeley made people track lights then describe the shape in the middle, found that participants couldn’t intake a dual task as the visuo-spatial sketchpad was overloaded, but a visual and verbal task combination would have worked
• - Doesn’t include three types of LTM (use LTM study as evidence)
• + More detailed than MSM, higher face validity
Describe and evaluate interference as an explanation of forgetting
AO1
• Interference- being unable to access the memories even though they are available
• Retroactive interference- when a new memory interferes with an old memory
• Proactive interference- when an old memory interferes with a new memory
• Interference is worse when memories are similar
• McGeoch and McDonald gave groups a list of words to recall. They then gave them either a list of synonyms, antonyms, unrelated words, nonsense syllables,3 digit numbers, or the same list to remember, then asked them to recall the original list. More similar words lead to worse performance
AO3
• + Lab study- lab experiment, variables controlled so high internal validity
• - Lacks generalisability as participants may not behave naturally due to demand characteristics, so has low internal validity
• + Baddeley and Hitch asked rugby players to remember names of teams they had played week by week. Some players had missed games, and recall was better if they had played no matches since then (retroactive interference, no new similar information)
• - Lower face validity than retrieval failure
Describe and evaluate retrieval failure as an explanation for forgetting
AO1
• Retrieval failure- a form of forgetting occurring when we don’t have the necessary cues
• Encoding specificity principle- if a cue is provided to help us recall information it has to be present at encoding and retrieval
AO1- context dependent
• Cue is location, location where information is encoded needs to be the same as where it is retrieved
• Godden and Baddely had groups of divers recall words, group 1 learnt and recalled on land, group 2 learnt underwater and recalled on land, group 3 learnt on land and recalled underwater, group 4 learnt and recalled underwater
• Groups 1 and 4 recalled the best, accurate recall was 40% lower in the non-matching environments
AO3
• + Field experiment- high ecological validity as participants were divers so are in this situation often
• - Field experiment- lack of control over control variables
• - Not often that something is learnt in one location and recalled in an entirely different location
AO1- state dependent
• Cue is how you feel (state), state in which information is encoded needs to be the same as when it is retrieved
• Carter and Cassaday gave participants anti-histamine tablets which make them drowsy, group 1 learnt and recalled on the drug, group 2 learnt not on the drug and recalled on the drug, group 3 learnt on the drug and recalled not on the drug, group 4 learnt and recalled not on the drug
• Group 1 and 4 recalled the best
AO3
• + Baker et al made people chew and not chew gum, after 24 hours, recall out of 15 was best for the groups with gum-gum and no gum-no gum
• - Godden and Baddeley’s replication of underwater study with recognition and found it didn’t affect recognition of words, so it lacks generalisability as it can’t be applied to all recall
Describe and evaluate research into the influence of misleading information on the accuracy of eyewitness testimony
AO1- Leading questions
• A question which is phrased in a certain way to lead you to a certain answer
• Loftus and Palmer showed the participants a video of a car crash and asked the speed the car was going when it hit, contacted, bumped, collided or smashed into the other car
• The mean speed for contacted was 31.8 mph, smashed was 40.5mph
AO3
• + Lab experiment- variables controlled so high internal validity
• - Lab experiment- low ecological validity due to watching a video not stimulating the same emotional effects as a real crash
AO1- Post-event discussion
• Witnesses discuss what they have seen after an event which may influence the accuracy of their recall
• Gabbert et al showed participants videos of the same crime filmed from different angles so they could see different things, then discuss what they had seen before a recall test
• 71% of participants recalled information that they did not see, compared to 0% in the control group who had no post-event discussion
AO3
• + Bodner found recall was more accurate if participants were warned of the effects of post-event discussion
• - Zaragosa and McCloskey say many answers given in lab studies of EWT are due to demand characteristics, as they don’t want to let anyone down, so may just guess answers
Describe and evaluate research that has investigated the influence of anxiety on the accuracy of eyewitness testimony
AO1
• Johnson and Scott, lab experiment. Both groups of participants heard a heated argument whilst in a waiting area, group 1 saw a man come out carrying a greasy pen, group 2 heard glass smash and saw a man come out with a blood covered knife
• Participants picked the man from a set of 50 photos, in group 1, 49% correctly identified him, in group 2, 33% correctly identified him
• Tunnel theory says witness’ attention narrows to focus on a weapon as it is a source of anxiety
AO3
• - Lab experiment- low ecological validity
• - Protection from harm was low due to anxiety, needed to offer counselling afterwards
• - Pickel put scissors, a wallet, a handgun and a chicken into a video of a hairdressers, eyewitness accuracy was poorer in the high unusualness conditions, may be testing surprise not anxiety
• Yulle and Cutshall questioned 13 witnesses 5 months after a shooting in a gun shop and compared answers with police interviews, and asked them to rate their anxiety. Witnesses’ accounts hadn’t changed much after 5 months, high stress was 88% accurate, low stress was 75% accurate
• + Field experiment- natural, high ecological validity
Describe and evaluate the cognitive interview as a way of improving the accuracy of eye-witness testimony
AO1
• Report everything- recall all information even if it seems insignificant
• Reinstate the context- this adds cues to help the witness retrieve information
• Reverse order- this reduces the likelihood of false information being stated
• Change perspective- this is to help the witness add detail to their information
• Enhanced cognitive interview- establish a rapport to calm the witness, establish eye contact, open ended questions
AO3
• - Time consuming, may require special training, so when it has been used by police, it is unlikely that the proper version would have been used, so the studies don’t have a high ecological validity
• + Milne and Bull, a combination of “report everything” and “reinstate the context” is the most useful
• + Kohnken et al did a meta-analysis of 50 studies, CI provided 81% correct information
• - Kohnken et al also found an increase of 61% in incorrect information
• - Every study uses a slightly different version of CI, so multiple CIs may be being tested, leading to low internal validity
