Lesson Two: Distinction between STM and LTMSpecification

A – Models of Memory

1. The multi-store model including concepts of encoding, capacity and duration. Strength and weaknesses of the model

2. The working memory model including its strengths and weaknesses

B – Memory in everyday life

1. Eyewitness testimony and factors affecting the accuracy of EWT including anxiety and age of witness

2. Misleading information and the use of cognitive interview

3. Strategies for memory improvement

Homework

Describe the evidence for a distinction between STM and LTM

Complete as much as possible of your key terms and key studies grids

Starter

Make a list of things you think are in your LTM, and imagine some that could

be in your STM

Lesson Objectives:

By the end of this lesson, you will be able to:

1. Describe the evidence for a distinction between STM and LTM

Key Words to check you know by the end of the lesson:

• Capacity• Duration• Free Recall• Primacy• Recency• Serial Position Curve

Let’s do something to demonstrate short-term and long term memory – take the face test

Oh! And put your hand up when we get to the Free Recall Task…

http://faculty.washington.edu/chudler/java/facemem.html

Demonstrating LTM

• Write down one statement/fact that you remember from primary school (i.e. something you learned about geography, history, maths…)

• Why do you remember this?• Lets look at the distinction between

STM & LTM…….

Free Recall Task

Glanzer and Cunitz (1966)

• Functional dissociation experiment.• Try and remember the items as they

appear.• Then (free recall) write down as

many things as you can remember

Condition 1 (no interference task)

• Distant• Stable• Cabbage• Mattress• Uncle• Minstrel• Question• Cottage• Bargain• Finger• Landscape• Future

Condition 2 – (Interference task) Now ………….

• First count backwards in three’s for 30 seconds

• Try and remember the items as they appear.

• Then count backwards in sixes for 30 seconds

Condition 2 (with interference task)

• Velvet• Stomach• Flower• Gossip• Chamber• Sandal• Warehouse• Village• Carpet• Favour• Lawful

Plot the position of each word in the list against how many of the participants

recalled it

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0.2

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0.8

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1.2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Position in List

Rec

all

Serial Position Demonstration

Position Recall cond. 1 Recall cond. 2

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2

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Pro

babili

ty c

orr

ect

Serial position

Glanzer & Cunitz (1966)%

reca

ll by P

Ps

Position in word list

With interference

task

Without interference

task

Primacy Effect: LTM

Recency Effect: STM

Glanzer & Cunitz (1966)

• Results:– Participants recalled more words at

beginning (primacy) and end (recency) of the list

– The interference task removed the recency but not the primacy effect

• Implies that primacy words were stored somewhere different to recency words

But how? • The recency effect – because words are still

circulating in the STM and can be easily retrieved

• The primacy effect – because words at the beginning of the list have rehearsed (repeated) and so have passed into LTM

• Displacement - Words in the middle are poorly recalled, little time for rehearsal & therefore displaced by later items in the list

• NOW – in your course pack grid write up what happened in this experiment.

• Extension – explain the relation on the line graph p9

Issues in Glanzer and Cunitz’ Study

• Methodology: Lab experiment– Reliability– Ecological Validity

• Participants had to repeat the task many times – what effect do you think this could this have had on the results?

• NOW - What other factors affect one part of the serial position but not the other? p9

Neuropsychological Evidence

• People who have suffered brain damage

• Selective Memory Loss – affecting one type of memory but not another

• TYPE OF RESEARCH – Case studies• What are these? P121• Evaluate the strengths and weaknesses

of this method of research in your course pack (10 minutes)

Task

• Now complete the sheet in your study pack on the cases of HM (Milner) and KF (Shallice & Warrington).

• What evidence does the case of HM

provide for functional dissociation? Discuss your answer with the person next to.

Alzheimer's Disease• Early symptoms include severe memory impairment

• WATCH CLIP: (19. Understanding Alzheimer's Disease Provides a clear demonstration of how the advent of new technologies has aided research into the etiology of disease.) http://www.learner.org/vod/vod_window.html?pid=1626

• Patients are found to have low levels of the neurotransmitter – acetylcholine – compared to controls.

• What did Drachman & Sahakian (1979) find out in their research? (Write this up on your study sheet)

Brain scanning techniques• PET – Position emission Tomography

• FMRI – Functional magnetic resonance imaging

• Squire et al. (1992)• (Write this up on your study• sheet)

Activated in STM tasks

Activated LTM tasks

Check your key words:

• Capacity• Duration• Free Recall• Primacy• Recency• Serial Position Curve

Check your

understanding

• In no more than 5 lines explain the evidence for separate memory stores

• Test your memory - try not to look at your notes…..

Can you suggest reasons why this task was difficult/easy for you.

Describe the evidence for a distinction between STM and LTM

Eye on the exam • The following are all concepts related to memory:

a.) Durationb.) Capacityc.) Encodingd.) RetrievalIn the table below write which one of the concepts listed above

(a,b,c, or d) matches each definition

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

Short-term memory Long-term memory

Capacity

Duration

Encoding Mainly acoustic Mainly semantic

Definition Concept

The length of time the memory store holds information

Transforming incoming information into a form that can be stored in memory