• Models of memory– The Multi-Store model including the concepts of

encoding capacity and duration. • Strengths and Weaknesses of the model

– The working memory model • Strengths and weaknesses of the working memory model

• Memory in everyday life– Eyewitness testimony– factors affecting the accuracy of EWT, including

anxiety, age of witness

• Misleading information and the use of the cognitive interview

• Strategies for memory improvement

AS AQA A Cognitive Psychology

Lesson FOURLesson FOURFactors affecting encoding and

Evaluating the Multi-Store Model!

Lesson Objective:

By the end of this lesson, you should be able to…

• Describe what is meant by encoding in LTM

• Evaluate the Multi-Store Model of Memory

Key Words

• Encoding

• Acoustic

• Visual

• Semantic}

Link to last lesson:

• Answer the following questions:

• How are the concepts of capacity and duration applied to STM stores?

• What factors affect capacity and duration in STM?

• How have they have been measured?

Link to last lessonEye on the exam

• Below is a table summarising the main differences between short term memory and long term memory. Complete the table. (2 marks)

STM LTM

Capacity

Duration

Encoding Mainly acoustic Mainly semantic

Discuss with the person next to you

The photo/item that you have brought in.

What do you think are the main details that help you remember your first memory?

Our brain has a few different ways of transferring information from STM to LTM…

When information arrives in sensory memory……

• E.g. Visual image or acoustic sound…• Sensory store has separate stores for different

modalities (sensory experience such as vision, sound, touch)

• Atkinson & Shiffrin – STM as a unitary store (no separate compartments)

• So what happens to the stimulus once it arrives in STM….

Likely that it is recoded…..

• Into a form that STM can recognise and manipulate

• Three main types of encoding used in STM:

• Acoustic Coding (hearing/sounds) (main way)

• Visual Coding (seeing/pictures/shapes)

• Semantic Coding (meaningful experiences)

Much of the evidence on encoding……

• Comes from studies into substitution errors

• When using a particular code, people may confuse– items that sound alike – acoustic code– Items that look similar – visual code – Items that mean the same thing – semantic

code

Evidence for types of Coding in STM: Conrad (1964)

• Consonants flashed very quickly in random sequence onto a screen

Two conditions:– Acoustically similar: B, G, C, D, T, V– Acoustically dissimilar: F, J, X, M, L, R

• Participants asked to write down consonants in the correct serial order

Evidence for types of Coding in STM: Conrad (1964)

• Findings:

• Ps made errors in substituting similar-sounding letters in the ‘similar’ condition

• So….

• Conclusion:We convert visual information into acoustic code in STM

and we then find it difficult to distinguish between words that sound the same – there is acoustic confusion

Methodological Issues in Conrad (1964)

• Lab Experiment – Strengths + Weaknesses?

• Artificial stimuli

• Ethics: Informed consent and debriefing

Posner & Keele (1967)Do the letters have the same name?

• B• b

• B• B

• A• B

• A• a

Condition 2

• D• d

• G• G

• H• H

• I• J

Posner & Keele (1967)

• People took longer to respond to B – b than B – B if the delay between the two letters was less than 1.5 seconds.

• Conclusions: Visual code had been stored in STM for a brief period and is soon translated into an acoustic code

• So STM codes…………………………….

Encoding in LTM

• Remember the ‘first memory’ task at the beginning of the lesson?

• What helped you remember this?

• What does this memory mean to you?

Encoding in LTM mainly semantic: based on the meaning of what is experienced

Baddeley (1966) Try and memorise the following words…

Then write down in serial order…List 1: man map can capList 2: try pig hut penList 3: great big huge wideList 4: run easy tug end

Did you notice anything? Whose research does this support?

Baddeley (1966) modified to test LTM

• He extended word lists from 5 to 10 and prevented rehearsal by interrupting Ps after each presentation.

• Each list presented x4 and recall tested after 20 minute interval

• FINDINGS: Acoustic similarity had no effect on recall. Words similar in meaning were poorly recalled

• CONCLUSION: LTM codes………………..

Methodological Issues

• Laboratory experiment: S + W’s

• However: familiar words rather than consonants (like who used)!

• Ethics: informed consent and debriefing

Application to real life

• Peter was trying to remember the name of his first teacher at primary school without success. Then his mother managed to find a class photo which she showed Peter. The name of his teacher then popped into his mind’. Explain why was Peter was suddenly able to remember.

» 5 minutes

Test your LTM ……

• Can you imagine what this might sound like? (Acoustic)

• Can you imagine this place? (Visual)

• So this suggests that semantic coding is not the only type in LTM.

Evaluating the Multi-Store Model of Memory – sort task

• The strengths and weaknesses on the handout have been jumbled up

• You need to put them into the correct category (strength or weakness) and

• Match the evidence to each point!

Check you understanding

• Using your textbook write a response to the following claim:

• ‘The multi-store model was very influential at one time but it has outlived its usefulness’. – Do you agree, if so what evidence is there?

Eye on the exam

• The multi-store model of memory has been criticised in many ways. The following example illustrates a possible criticism.

• Some students read through their revision notes lots of times before an exam but still find it difficult to remember the information. However the same students can remember the information in a celebrity magazine even though they read it only once.

• Explain why this can be used as a criticism of the multi-store model. ((((((((4 marks))))))))

M-SM Memory – fill in the blanks• The model arose from the information processing approach where memory is characterised as a flow of

information through a system. The system is divided into a set of stages and information passes through each stage in a fixed sequence.

• There are capacity and duration limitations at each stage.

• Transfer of information between stages may require re-coding.

• External stimuli from the environment first enter sensory memory, where they can be registered for very brief periods of time before decaying (i.e. fading away) or (if given attention) being passed onto the short term store.

• STM contains only the small amount of information that is actually in active use at any one time. Information is usually encoded acoustically at this stage.

• Memory traces in STM are fragile and can be lost within about 30 seconds, through displacement or decay, unless they are repeated (rehearsed).

• Material that is rehearsed is passed onto the long term store where it can remain for a lifetime, although loss is possible from this store through decay, retrieval failure or interference.

• Coding in LTM is assumed to be in terms of meaning, i.e. semantic.

HomeworkEye on the exam

Outline and evaluate the multi-store model of memory (12 marks)