Get Started. It's Free
or sign up with your email address
Memory by Mind Map: Memory

1. Capacity

1.1. STM

1.1.1. Jacobs (1887) used the digit span test to find that the average capacity for digits was 9.3 items and 7.3 for letters

1.2. LTM

1.2.1. Miller (1956) found the 'Magic Number' which is 7 +/- 2

2. Duration

2.1. STM

2.1.1. Peterson and Peterson (1959) found that the duration of STM is up to 18 seconds

2.2. LTM

2.2.1. Bahrick et al. (1975)found that the duration of LTM is potentially unlimited

3. Coding

3.1. Acoustic and Semantic Coding

3.1.1. Baddeley (1966a and 1966b) used word lists to test the effects of acoustic and semantic similarities on STM and LTM. He found that STm is largely encoded acoustically whereras LTM is largely encoded semantically.

3.2. The Difference Between Acoustic and Semantic

3.2.1. The following words are acoustically similar but semantically different: cat, cab, can, cad, cap, mad, max, mat, man, map.

3.2.2. The following words are semantically similar but acoustically different: great, large, big, huge, broad, long, tall, fat, wide, high.

4. The Multi-Store Model of Memory

4.1. Atkinson and Shiffrin (1968)

4.2. This consists of three memory stores which are linked together by the processes that enable the transfer of information from one store to the next.

4.2.1. Memory Stores Sensory Register The place where information is held at each of the senses and the corresponding areas of the brain. The capacity at these registers is very large. The sensory registers are constantly receiving information, but most of this receives no attention and remains in the sensory register for a very brief duration (milliseconds) Short-Term Memory Information is held in STM so it can be used for immediate tasks. It has a very limited duration, it decays very quickly if it isn't rehearsed. Information also disappears from here if new information enters (it is displaced) because STM also has a limited capacity. Long-Term Memory LTM is potentially unlimited in duration and capacity. Evidence suggests that if you forget something you never really made the memory permanent, or it there you just can't find it.

4.2.2. Processes Attention If a person's attention is focused on one of the sensory stores, then the data is transferred to STM. Attention is the first step in remembering something. Maintenance Rehearsal Repetition keeps information in STM but eventually such repetition will create a LTM. Retrieval The process of getting information from LTM that involves the information passing back through STM. It is then available for use.

5. The Working Memory Model

5.1. Baddeley and Hitch (1974)

5.2. This model suggests that there is one store for visual processing and a seperate store for processing sounds. This forms the basis of the WMM where 'slave systems' are organised by a central executive.

5.2.1. Central Executive Monitors and Coordinates all other mental functions in working memory.

5.2.2. Phonological Loop Codes speech sounds in working memory, typically involving maintenance rehearsal. This is why this component of working memory is referred to as a 'loop'

5.2.3. Visuo-Spatial Sketchpad Codes visual information in of separate objects as well as the arrangements of these objects in ones visual field

5.2.4. Episodic Buffer Receives input from many sources (general store), temporarily stores this information, and then integrates it in order to construct a mental episode of what is being experienced

6. Types of Long-Term Memory

6.1. Episodic Memory

6.1.1. These are about knowing that. These are memories of events and personal experiences. This also includes the surrounding context around the event as well as the the emotions associated with the event

6.2. semantic Memory

6.2.1. These are also knowing that. But these are memories of facts, they are usually acquired through episodic memories because we acquire knowledge through personal experience

6.3. Procedural Memory

6.3.1. This is the memory of skills, these are typically acquired through repetition and practice, unlike episodic and semantic memory these memories are usually implicit. We are less aware of these memories because they become automatic.

7. Explanations for Forgetting

7.1. Interference

7.1.1. Retroactive Interference Muller and Pilzecker (1900) were first to identify the effects of this type of interference. This is when current attempts to learn something interfere with past learning.

7.1.2. Proactive Interference Benton Underwood (1957) showed that this interference could be equally significant. This is when past learning interferes with current attempts to learn something.

7.2. Retrieval Failure

7.2.1. The Encoding Specificity Principle Endel Tulving and Donald Thomson (1973) proposed that memory is most effective if information that was present at encoding is also available at the time of retrieval. This principle further states that the cue doesn't have to be exactly the same but the closer it is the more useful.

7.2.2. Context-Dependent Forgetting Ethel Abernathy (1940) researched this and found that the environment and context effect the recall of memories

7.2.3. State-Dependent Forgetting Goodwin et al (1969) found that ones emotional state also effects the recall of memories.

8. Eyewitness Testimony

8.1. Misleading information

8.1.1. Loftus and Palmer (1974) - Leading Questions Procedure Participants where shown different films of traffic accidents, they were then given a questionnaire that asked them to describe the accident and answer a series of questions about it. There was one critical question: 'How fast was the cars going when they hit each other?' One group was given this question, the other 4 groups were given this question with the verbs smashed, collided, bumped or contacted in the place of hit. This made the question a leading question. Findings Here are the findings which demonstrate that leading questions affect the response given: Verb Mean Speed Estimate Smashed 40.8 Collided 39.3 Bumped 38.1 Hit 34.0 Contacted 31.8

8.1.2. Post-Event Discussion Conformity Effect Co-witnesses may reach a consensus of what actually happened. Gabbert et al. (2003) investigated this and found that 71% of witnesses that discussed the events went on to mistakenly recall items acquired during the discussion Repeat Interviewing Each time an eyewitness is interviewed there is a possibility that comments from the interviewer will become incorporated into their recollection of events.

8.2. Anxiety

8.2.1. Anxiety has a Negative effect on Accuracy Stress (and anxiety) has a negative effect on memory as well as performance generally. Automatic skills are not affected by stress/psychological arousal but performance on complicated cognitive tasks is reduced by stress.

8.2.2. Johnson and Scott (1976) Procedure To test the weapon focus effect, participants were sat in a waiting room where they heard an argument in the adjoining room and then saw a man run through the waiting room carrying either a pen covered in grease (low anxiety condition) or a knife covered in blood (high anxiety condition). The participants were later asked to identify the man from a set of photographs. Findings The findings supported the weapon focus effect, mean accuracy was 49% in the low anxiety condition, compared with 33% in the high anxiety condition.

8.2.3. Anxiety has a Positive Effect on Accuracy There is an alternative argument that says high anxiety creates more enduring and accurate memories. Christianson and Hubinette (1993) found evidence of enhanced recall when they questioned witnesses of real bank robberies in Sweden. The witnesses were either victims (high anxiety) or bystanders (low anxiety) and were conducted 4-15 months after. There was better than 75% recall and those who were most anxious had the best recall

8.2.4. Resolving the Contradiction Kenneth Deffenbacher (1983) Deffenbacher reviewed 21 studies of the effect of anxiety on eyewitness memory. He found that 10 of these studies had results that linked to higher arousal levels to increased eyewitness accuracy and 11 showed the opposite. Deffenbacher then suggested the Yerkes-Dodson effect can account for this apparent inconsistency. According to this there would be occasions when anxiety/arousal is only moderate and then eyewitness accuracy is enhanced. When anxiety/arousal is too extreme then accuracy will be reduced. Deffenbacher then suggested the Yerkes-Dodson effect can account for this apparent inconsistency. According to this there would be occasions when anxiety/arousal is only moderate and then eyewitness accuracy is enhanced. When anxiety/arousal is too extreme then accuracy will be reduced.

8.3. The Cognitive Interview, Geiselman et al. (1984)

8.3.1. 1. Mental Reinstatement of Original Context The interviewer encourages the interviewee to mentally recreate both the physical and psychological environment of the original incident. The aim is make the memories accessible, people often need appropriate contextual and emotional cues to retrieve memories.

8.3.2. 2. Report Everything The interviewer encourages the interviewee to report every detail of the event without editing anything out, even though it may seem irrelevant. Witnesses should not leave anything out. Memories are interconnected with one another so the recollection of one event may cue a whole lot of other memories.

8.3.3. 3. Change Order The interviewer may try alternative ways through the timeline of an incident, for example by reversing the order in which the event occurred. This is because our recollections are influenced by schemas.

8.3.4. 4. Change Perspective The interviewee is asked to recall the events from multiple perspectives, for example by imagining how it would have appeared to another witness present at the time. This is again done to disrupt the effect that schemas have on recall.