Memory

Coding - the way information is changed so that it can be stored in memory.

Capacity - this is a measure of how much can be held in memory.

Duration - a measure of how long a memory lasts before it is no longer available.

Coding:

• Visually - remembering images.
• Acoustically - remembering sounds and words.
• Semantically - remembering the meanings of things.

Baddeley (1966): discovered that coding in STM is mainly acoustic. He gave participants acoustically similar words to learn in one condition and compared the recall with other groups given dissimilar words. He found that the similar-sounding words were least well recalled (10%), with the other lists recalled between 60 and 80%. He suggested that this shows coding is acoustic because of the confusion caused when coding the words.

Capacity:

For STM, it is limited to between 5 and 9 items, however, we can use chunking to increase the capacity.

Miller (1956): 'the magical number 7, +/- 2' was the title. He suggested that the average span for letters and numbers was 7, but that this could be increased by chunking.

Duration:

A maximum of 30 seconds, but it can be extended by repetition or rehearsal.

Peterson & Peterson (1959): they got participants to learn the trigrams and then count backwards from a three-digit number until told to stop. They tested recall of the trigrams after 3, 6, 9, 12, 15 or 18 seconds, which they called the retention interval. They found that STM declined rapidly without the benefit of rehearsal.

Coding:

• Visually - remembering places, faces.
• Acoustically - remembering songs, voices.
• Semantically - the main way information is remembered in LTM is through its meaning.

Frost (1972): used a free recall task to show that participants used both visual and semantic coding. This depended on whether they were expecting to recall or recognise visually or semantically categorised pictures or picture names. He found that parallel access of visual and semantic memory codes occurred. When reocgnition is expected, a visual cue provides faster access; when expecting recall, verbal access is more efficient. This demonstrates that separate coding occurs.

Capacity:

Thought to be unlimited, depending on individual differences. However, decay, interference and illness may result in the loss of information.

Ramscar (2014): 'trained' computers to mimic elderly people's brains. He found that as the computers 'aged' by acquiring more and more information, they slowed down. The research suggests that human brains slow down because they are filling with information. An elderly person has to sift through much more knowledge to find a name or date, which appears to make them slow.

Duration:

No upper limit.

Bahrick (1975): asked people to put names to faces from their school yearbook. Those who had left 48 years previously were very accuate (70%). They were less accurate in the free-recall condition in which they had to recall their peers without seeing the yearbook (30%). This shows that memory for faces is very good, but that recognition is easier than recall. Most of the time we use recognition, which could explain why straight recall of facts in exams is more challenging.

Multi-store model - an explanation of memory based on three separate memory stores, and how information is transferred between these stores.

1. Sensory register - is the place where information is held at each of the senses.

2. 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.

3. Short-term memory - information is held in STM for immediate tasks.

4. Maintenance rehearsal - repetition keeps information in STM, but eventually such repetition will create a long-term memory (LTM).

5. Long-term memory - LTM is potentially unlimited in duration and capacity.

6. Retrieval - the process of getting information from LTM involves the information passing back through STM. It is then available for use.

+ Case study - the case study of HM, who lost his hippocampus in an operation leaving him unable to learn new things in LTM while retaining the ability to remember short strings of digits in STM, indicates there are two separate stores.

- Scanning techniques research - more recent research using scanning techniques is showing that the idea of just three storse is too simple. There are LTMs for episodic, procedural and semantic memory and scans show that these are distinctiely different.

- LTM involves more than maintenance rehearsal - research suggested that enduring memories are created by the processing that you do, rather than through maintenance rehearsal; things that are processed more deeply are more memorable just because of the way they are processed.

Working memory model - an explanation of the memory used when working on a task. Each store is qualitatively different.

The central executive monitors and coordinates all other mental functions in working memory. It has a limited capacity.

The phonological loop codes speech sounds in working memory, typically involving maintenance rehearsal.

The visuo-spatial sketchpad codes visual information in terms of separate objects as well as the arrangement of these objects in one's visual field.

The episodic buffer receives input from many sources, temporarily stores this information, and then integrates it is in order to construct a mental episode of what is being experienced.

+ Dual task performance - Baddeley and Hitch, found that both the central executive and the articulatory loop were involved and this demonstrates the dual task performance effect and also shows that the central executive is one of the components of working memory.

- The central executive - there is some concern about the central executive; about what it is.The answer appears to be that it allocates resources and is essentially the same as 'attention'. Some psycholgists feel this is too vague and doesn't really explain anything.

- Evidence from brain-damaged patients - the process of brain injury is traumatic, which may in itself change behaviour so that a person performs worse on certain tasks. Some individuals may have other difficulties, like difficulties paying attention and therefore, underperform on certain tasks.

Episodic memory - personal memories of events, such as what you did yesterday or a teacher you liked. This kind of memory includes contextual details plus emotional tone.

Procedural memory - memory for how to do things, for example, riding a bike or learning how to read. Such memories are automatic as the result of repeated practice.

Semantic memory - shared memories for facts and knowledge. These memories may be concrete, such as knowing that ice is made of water, or abstract, such as mathematical knowledge.

+ Evidence - there is now strong evidence for different memory types with the availability of scanning technology. This has increased the reputation of psychology as a science.

+ Distinguishing episodic and semantic memories - researchers have studied patients with Alzheimer's disease and found some patients who retain the ability to form new episodic memories, but not semantic memories. This is a single dissociation; a separation between the two.

Interference - an explanation for forgetting in terms of one memory disrupting the ability to recall another. This most likely to occur when the two memories have some similarity.

Proactive interference - past learning interferes with current attempts to learn something.

Retroactive interference - current attempts to learn something interfere with past learning.

Supporting evidence - McGeoch and Mcdonald (1931): 6 groups had to learn 10 adjectives perfectly. They then had to learn a new list that had a similar meaning, opposite meaning or there were various controls, such as nonsense syllables or a rest with no learning.

Results: performance depended on which second list they experienced and whether it interferred with the learning of the adjectives. Those in the rest condition did best because there was no interference and those in the synonym condition performed poorly.

Conclusion: the similarity of the synonyms created greater interference, causing more forgetting.

+ Reliable - lots of laboratory studies high control and standardised procedures mean they are reliable findings.

+ Real life applications - the findings are easily applied to real life and are useful in improving retention in memory by avoiding learning similar items at the same time.

- Lack validity - the tasks can be criticised for lacking in validity or mundane realism. For example, learning nonsense syllables is never done normally.

Retrieval failure - occurs due to the absence of cues. An explanation for forgetting based on the idea that the issue relates to being able to retrieve a memory that is there, but not accessible.

The encoding specificity principle states that a cue doesn't have to be exactly right, but the closer the cue is to the oginal iem, the more useful it will be.

Cues - things that serve a reminder.

- Laboratory research - much laboratory research, which lacks mundane realism. Real-life memories are likely to have multiple cues when coding and recall.

- The danger of circularity - Nairne (2002) has criticised what he calls the 'myth of the encoding-retrieval match'. He claims that the relationship between encoding cues and later retrieval is a correlation rather than a cause; cues do no cause retrieval, they are just associated with retrieval.

+ Real-world application - Smith (1979) showed that just thinking of the room where you did the original learning was as effective as actually being in the same room at the time of retrieval.

Eyewitness testimony - the evidence provided in court by a person who witnessed a crime, with a view to identifying the perpetrator of the crime.

Misleading information - supplying information that may lead a witness' memory for a crime to be altered.

Leading question - a question that suggests to the witness what answer is desired or leads them to the desired answer.

Post-event discussion - a conversation between co-witnesses or an interviewer and an eyewitness after a crime has taken place which may contaminate a witness' memory for the event.

Supporting study - Loftus & Palmer (1974):

Procedure: 150 participants were shown a video of a car accident. They were asked about the speed. They were told to return 1 week later when they were asked a series of questions (10). "Did you see any broken glass?" - there wasn't any.

Findings: people who had the word 'smashed'or 'hit', said 41 mph.

Conclusion: they show the impact of leading questions and that people have schemas.

+ Useful - this research is very useful when applied to the criminal justice system and it has led to improvements in procedures.

- Artificial research - early research was very artificial and laboratory-based. For example, Loftus car crash work used police crash videos lasting a few seconds and had limited samples so was lacking validity and generalisability.

Anxiety - an unpleasant emotional state that is often accompanied by increased heart rate and rapid breathing.

Supporting evidence - Johnson and Scott (1976):

Procedure: participants sat in a waiting room where they heard an argument in an adjoining room and then saw a man run through the room carrying either a pen covered in grease or a knife covered in blood. They had to identify the man from photos.

Findings: the mean accuracy was 49% in identifying the man in the pen condition, compared with 33% accuracy in the knife condition.

+ Real-life - this research has added to our understanding of what happens to real-life witnesses and has increased the crediblity in court even if they were scared at the time.

- Ethics - asking someone to re-live a crime they saw can be distressing for the witness.

- Extraneous variables - real-life studies lack the controls of laboratory experiments. Extraneous variables may interfere with the results, For example, witnesses could have discussed what they saw and altered their memory of the events.

Cognitive interview - a police technique for interviewing witnesses to a crime, which encourages them to recreate the original context of the crime in order to increase the accessibility of stored information.

1. Mental reinstatement of original context: interviewee mentally recreates both the physical and psychological environment of the original incident.

2. Report everything: interviewee is encouraged to report every detail of the event.

3. Change order: the interviewer may try alternative ways through the timeline of the incident.

4. Change perspective: interviewee recalls the incident from multiple incidents.

+ Real-life - it has helped with the training of police officers and is used often.

- Individual differences - it may only work for some individuals; not everyone.