Memory

Question 1

MSM: what is the capacity, duration and coding of the sensory register?

Answer 1

Capacity: Sperling (1960) pts presented with a 3x4 letter grid for 1/20th second. When a high, medium or low pitched tone was produced to indicate which row was to be recalled pts scored 3/4. Since pts did not know which row they had to recall the information had to be available somewhere. Capacity of sensory register is unlimited.
Duration: 250 milliseconds.
Coding: modality specific. There are separate sensory stores for different sensory inputs: Echoic (sound), Haptic (touch), Iconic (sight), Olfactory (smell), Gustatory (taste)

Question 2

MSM: what is the capacity, duration and coding of STM?

Answer 2

Capacity: Miller (1956) reviewed studies looking at capacity and found STM has a capacity of 7+ or - 2.
Duration: Peterson and Peterson (1959) pts were shown a trigram. Rehearsal was prevented by having pts count backwards in 3’s, in intervals of 3,6,9,12 and 18 seconds. Pts then asked to stop counting and repeat the trigram. Found that after 18 seconds the % recalled correctly was very low, showing the memory of the trigram had decayed. Duration of STM is 18-30 seconds.
Coding: Baddeley (1966) 75 pts presented with word lists that were acoustically similar and dissimilar and asked to remember it. Pts were then given the list in the wrong order and asked to reorder the list immediately. Found that there was acoustic confusion with words that sounded the same. STM codes acoustically.

Question 3

MSM: what is the capacity, duration and coding of LTM?

Answer 3

Capacity: is potentially unlimited.
Duration: Bahrick et al (1975) showed 400 pts a set of photos and a list of names. Asked to identify their old school friends. Those that had left school 48 years ago recalled 80% of names and 70% of faces. Duration of LTM is potentially forever.
Coding. Baddeley (1966) 75pts presented with word lists that were semantically similar/dissimilar and asked to remember them. Then given the lists in the wrong order and asked to reorder them after a 20 minute interval. Found that there was semantic confusion with words that had the same meaning. LTM codes semantically.

Question 4

MSM: evaluation?

Answer 4

+ Brain scans. Different areas of the brain are active when doing different types of memory tasks. Physical evidence for separate stores.
+ Case studies. H.M had his hippocampus removed and was unable to form new LTMs, although his STM was unaffected. Must be separate stores.
- Stores are not unitary. Evidence from H.M shows that there are different types of LTM. He could form new procedural LTMs. Not unitary.
- Different forms of rehearsal. Craik and Lockhart (1972) found that depth of learning leads to LTM rather than simple repetition. MSM is too simplistic by suggesting it is just rehearsal.
- Some things are just recalled more easily even without rehearsal and the MSM does not account for this. It is too simplistic.

Question 5

Types of LTM: what are the three types of LTM?

Answer 5

Episodic: memory for life events. Information stored with reference to time and place. Memories can be expressed verbally and are available for conscious inspection.
Semantic: memory facts and general knowledge. Information is available for conscious inspection and can be expressed verbally.
Procedural: memory for motor skills and muscle memory. Memories are not available for conscious inspection and are difficult to express verbally. Information is more resistant to forgetting/amnesia.

Question 6

Types of LTM: what evidence is there for the types of LTM?

Answer 6

+ Brain scan studies. Shows that different types of LTM are stored in different parts of the brain. Episodic and semantic are stored in the prefrontal cortex and procedural in the cerebellum and the basal ganglia.
+ Case studies. Clive Wearing lost all his episodic and most of his semantic memory but not procedural memory. This provides support for the different types of LTM.
+ H.M.

Question 7

Working Memory Model: who proposed the working memory model? What are the components?

Answer 7

Alan Baddeley and Graham Hitch (1974).

Central executive. Episodic buffer. Phonological loop. Visio-spatial sketch pad. Phonological store. Articulatory process. Visual cache. Inner scribe.

Question 8

Working Memory Model: what is the role of the central executive?

Answer 8

The central executive controls three ‘slave systems’. It is a supervisory component that decides which information is and is not attended to. Had a limited capacity and can only attempt to a limited number of things at one time.

Question 9

Working Memory Model: what is the role of the phonological loop?

Answer 9

Deals with auditory based information. Phonological store - short term storage system. Articulatory process - active rehearsal system that allows information to be kept in the memory through sub-vocal repetition.

Question 10

Working Memory Model: what is the role of the Visio-spatial sketchpad?

Answer 10

Helps people navigate and interact with their physical environment. Visual cache - temporary visual store. Inner scribe - rehearsal mechanism.

Question 11

Working Memory Model: what is the role of the episodic buffer?

Answer 11

A temporary store responsible for integrating the visual, spatial and verbal information from other stores into a coherent episode. Has a limited capacity of 4 chunks.

Question 12

Working Memory Model: evaluation?

Answer 12

+ Evidence to support from the dual task studies. Baddeley at al found that it was harder to carry out two visual tasks (condition one) than visual and verbal tasks (condition two). Because in condition one the two visual tasks were competing for the same limited resources of the Visio-spatial sketchpad. Whereas, condition two was using separate resources. Shows different components.
+ Support from case studies. K.F. Suffered brain damage and had poor STM ability for verbal information but could process visual information. So, only his phonological loop had been damaged, which provides evidence for the different stores.
+ Practical applications. Working memory capacity can be used to measure suitability for certain jobs. US Air Force used WM capacity to assess pilots. This means the model has uses in the real world, increasing the validity.
- The model doesn’t account for musical memory because pts can listen to instrumental music without impairing performance on other acoustic tasks. This means the model is incomplete.
- Lack of clarity of the central executive. The CE is the most important part of the model but it is the least understood and it’s function is vague and difficult to test. This means the working memory model has not been fully explained.

Question 13

Forgetting in LTM: what is interference? Two types of interference?

Answer 13

Interference is when two memories become confused with each other, resulting in forgetting one or both pieces of information.
Proactive interference - old learning prevents the recall of new information. Older memories disrupt the recall of newer memories.
Retroactive interference - new learning prevents the recall of old information. Newer memories disrupt the recall of older memories.
Interference is much more likely when two lots of information are similar. It is less likely that interference will occur when there is a gap between instances of learning.

Question 14

Forgetting in LTM: what are the evaluation points for interference?

Answer 14

+ Supporting evidence. McGeoth and McDonald. Pts learn list of 10 words. Then learn a new list, either synonyms or 3 digit numbers. 12% recall on synonyms and 37% recall on 3 digit numbers. Shows interference is strongest when info is similar, supports retroactive interference.
+ Study found that the more times people moved house, the more street names they forget. Can be applied to real life.
+ Practical applications. Knowledge of interference effects can help revision strategies - don’t revise similar subjects close together. Can be applied to real life.
- Artificial nature of lab experiments. Stimuli involves word lists and these do not reflect all things learnt in real world settings. Low ecological validity, doesn’t explain it in real life.
- Other explanations. Like retrieval failure. This means interference may not be the most valid explanation.

Question 15

Forgetting in LTM: what is retrieval failure?

Answer 15

Retrieval failure is when information is available but cannot be accessed due to an absence of appropriate cues. A cue is a trigger of information that allows us to access a memory.
Types of cues:
Context - forgetting can occur when the external environment is dissimilar at recall.
State - forgetting can occur when the internal environment is dissimilar at recall e.g. being intoxicated or anxious.
Organisation - forgetting is less likely to occur when material is organised into categories as organisation can create cues.

Question 16

Forgetting in LTM: what are the evaluation points for retrieval failure?

Answer 16

+ Support for context. Godden and Baddeley tested forgetting in deep sea divers. Learn on land recall on land. Learn on land recall underwater. Recall 40% lower when context different.
+ Support for state. Overton got pts to learn material when drunk or sober. Recall was worse when the state was different. Valid as it happens in real life situations.
+ Practical applications. Used to improve eyewitness testimony. Reinstating the context is one of the 4 key principles. Has uses in the real world.
- The environment has to be very different to result in forgetting. Recalling in a different room is unlikely to lead to much forgetting. Can’t always be applied to everyday life instances of forgetting.
- Other explanations. Interference.

Question 17

EWT: what are the two factors affecting the accuracy of eyewitness testimony?

Answer 17

Misleading information

Anxiety

Question 18

EWT: Misleading information: what are leading questions? What are the two explanations for the influence of leading questions?

Answer 18

Questions that are worded or phrased in such a way that they bias the respondents answer. There are two explanations for the influence of leading questions:

1. Response bias explanation - wording of the question has no real effect on the pts memory but influences how they decide to answer.
2. Substitution explanation - working of the question actually changed the pts memory of the event.

Question 19

EWT: Misleading information: what is the supporting evidence for leading questions?

Answer 19

1. Loftus and Palmer - Experiment one. 45 pts had to estimate the speed of cars in films containing car accidents. Pts divided into 5 conditions. Asked ‘how fast was the car going when they hit each other’. Verb hit was replaced for each condition, by either: contacted/bumped/smashed/collided. Findings: contacted - 31.8mph. Smashed - 40.8mph. This supports the response bias explanation as it suggests that when a participant gets a leading question using the word ‘smashed’ they choose a higher estimate.
2. Loftus and Palmer - Experiment two. 150 pts divided into groups and shown a clip of car accident. Group one - ‘smashed’. Group two - ‘hit’. A week later all pts were asked ‘did you see any broken glass?’. Findings: Hit - 14% said they saw it. Smashed - 32% said they saw it. This supports the substitution explanation as the verb used altered their memory of the event.

Question 20

EWT: Misleading information: what is post-event discussion? What are the two explanations?

Answer 20

Post-event discussion happens when there is more than one witness to an event and they discuss what they have seen with each other. It can result in information being added after the event which will bias the witness testimony. There are two explanations:

1. Memory contamination - witnesses become confused about what they witnessed themselves and what others have told them.
2. Memory conformity - witnesses may go along with other people for social approval (NSI) it because they believe other witnesses have better information that them (ISI).

Question 21

EWT: Misleading information: what is the supporting evidence for post-event discussion?

Answer 21

Gabbert et al. Pts watched a video of a crime in pairs. Each pt watched the crime from a different perspective so each other could see elements in the event that the other couldn’t. Both pts then discussed what they had seen before individually completing a test of recall. Findings:

• 71% of pts mistakenly recalled aspects of the event that they did not see in the video.
• Compared to 0% in a control group with no discussion.

Question 22

EWT: Misleading information: evaluation?

Answer 22

+ Practical applications. Research can be applied to real EWT in police interviews. Useful in the real world.

• Lab studies lack ecological validity. The results may not be applicable to real life situations.
• Demand characteristics. Pts in a lab study may have acted differently to how they would in real life. Results may not be accurate and research into the effects of misleading information may not be useful.
• Small sample size. In Loftus and Palmer there were 9 pts per condition. Study lacks population validity and the results cannot be generalised to the whole population, meaning it may not be a useful explanation.

Question 23

EWT: Anxiety: what is the effect of anxiety on the accuracy of EWT?

Answer 23

There is conflicting evidence about the effect of anxiety on the accuracy of EWT.
A. Anxiety has a negative effect on recall: anxiety creates arousal in the body which prevents us from paying attention to important cues.
B. Anxiety has a positive effect on recall: the fight or flight response increases our alertness and improves our memory because we become more aware of the environment.
Yerkes-Dodson Law - explains this contradiction as it states that performance increases with arousal until a certain point and then it declines.

Question 24

EWT: Anxiety: what is the weapon focus effect?

Answer 24

Weapon focus effect - in violent crimes where a weapon is involved, anxiety may focus the witness on the weapon rather than other details of the event. This prevents recall and reduces accuracy of EWT.

Question 25

EWT: Anxiety: what is the supporting evidence for the effects of anxiety?

Answer 25

1. Johnson and Scott. Made pts believe they were in an experiment about human memory and were sat in a waiting room outside. Pts then heard discussion in another room. Condition one: discussion about equipment failure and a man left holding a pen with grease on his hands. Condition two: discussion more heated and man left holding a letter opener with blood on it. Findings:
   - Condition one: 49% correctly identified the man from 50 photos.
   - Condition two: 33% correctly identified.
   This supports the weapon focus effect as the weapon may have distracted attention from the person holding it. Supports the view that anxiety can reduce the accuracy of EWT and has a negative effect on recall.
2. Christianson and Hubinette. Carried out a survey of 110 people that had witnessed bank robberies. Some of these people had been bystanders and others had been directly threatened. They found that people who had been subject to the greatest anxiety showed more detailed and accurate recall. This suggests that high levels of anxiety can increase the accuracy of EWT and has a positive effect on recall.

Question 26

EWT: Anxiety: evaluation?

Answer 26

+ Johnson and Scott minimised demand characteristics that occur in controlled settings by using deception. Increases validity as pts did not know it was part of the experiment. Findings can be used to explain the effects of anxiety in real life.
- Christianson and Hubinette had a lack of control over extraneous variables as those who had experienced the most anxiety were also closer to the event. Not explained by anxiety but ability to see it clearly.
+ Real life applications. Led to the development of the cognitive interview. Has uses in the real world.
- Risk of psychological harm by asking people who have experienced violent incidents to recount their experience. Pts can’t give fully informed consent if deception is used. This means the research may be unethical abs so is not appropriate as evidence.

Question 27

Cognitive Interview: who was it developed by? What are the four aspects?

Answer 27

Fisher and Geiselman (1992).

1. Report everything. Every detail must be reported. In case details are overlooked.
2. Reinstate the context. Mentally reinstate the context of the crime. Including sights, sounds, feelings and emotions. Asked to recall the scene, the weather, thinking etc. Context provides cues, preventing retrieval failure.
3. Recall in reverse. Recount details of events in different orders moving backwards and forwards in time. Verifies the accuracy of the testimony.
4. Recall from a changed perspective. Report the incident from a range of perspectives including those of other bystanders or even the criminals. Promoted a more holistic view of the event.

Question 28

Cognitive Interview: evaluation?

Answer 28

+ Supporting evidence. Kohnken et al conducted a meta analysis and found the cognitive interview increases the number of correctly recalled details compared to a standard interview. CI is effective in improving EWT.
+ Further support. Milne and Bull found that each CI technique was equally effective. But a combination of all techniques was significantly more effective. CI as a whole is effective at improving EWT.
- Limitations. CI becomes less effective as time passes after the event. CI is only effective when the incident was recent and may not be useful for events that happened a while before the interview.
- Research in police departments has suggested that cognitive interviews are not used. Because it is time consuming as it takes longer than a standard interview and requires specialist training. Not the most practical technique to use in real life.