Transcript Nature of memory 2014

PSYA1:
Cognitive
Psychology
Memory
The Nature of
Memory
Experimental Methods (Lab,
Field, Natural)
Mrs Leach
The Specification
PSYA1 Memory
Let’s apply this to a Donut…
What is A01 and A02?
What is AO1 and AO2?
A02
Application & Evaluation
A01
Knowledge & Understanding
What is your opinion of the
Donut?
What are it’s strengths?
What are it’s weaknesses?
How does it compare to
other cakes?
What evidence is there for
and against this Donut?
Describe the Donut….
What is a Donut?
What shape is it?
What is it covered in?
What ingredients does it
contain?
These questions are designed for
you to demonstrate your
knowledge and understanding
of what a Donut is. You can do this
in an exam by describing or
outlining studies or theories. By
doing this you are showing you
know and understand!
3
These questions are designed to develop
your evaluation and critical thinking
skills. You can do this in the exam by
evaluating theories using strengths and
weaknesses.
You can also present research evidence to
support or refute.
You wake up one morning and you’ve lost your
memory. Try to answer the following questions:
1.
What do you normally do in a day that you would
no longer be able to do?
2.
What if you did not recognise your friends or family?
3.
What experiences would you miss if you couldn’t
remember TV programmes or news articles?
4.
How could you plan your day if you forgot what
you were thinking about a few minutes earlier?
How will I know if I am learning?
1.Describe STM in terms of capacity, encoding and
duration (AO1)
2.Describe LTM in terms of capacity, encoding and
duration (AO1)
3. To provide evidence in the form of studies for each
description. (AO2)
4.To explain what a lab experiment is and give
advantages and disadvantages (AO3)
Types of Memory
Rehearsal
Sensory
Memory
Encoding
Short
Term
Memory
Encoding
Retrieval
Long
Term
Memory
Evidence for STM and LTM
Now or Later? The “Recency/Primacy” Effect
(Murdock 1962)
 Based
on Murdock 1962 study. Laboratory
experiment. presented participants with a list of
words, one at a time, which they then recalled in any
order (free recall).
 Your
teacher is going to read you a list of 20 words,
your job is to remember as many of the words as
possible, as soon as your teacher has finished reading
them write them down straight away (silently, don’t
discuss or talk)
The “Primacy/Recency”
effect
You are now going
to analyse the
results. Your
teacher will
count up which
words the class
could remember.
Position
Word
1st
CAT
2nd
APPLE
3rd
BALL
4th
TREE
5th
SQUARE
6th
HEAD
7th
HOUSE
8th
DOOR
9th
BOX
10th
CAR
11th
KING
12th
HAMMER
13th
MILK
14th
FISH
15
BOOK
16
TAPE
17th
ARROW
18th
FLOWER
19th
KEY
20th
SHOE
Number of people in class that remembered it!
Now or Later? The
“Recency/Primacy” Effect
 Now
plot your results on a graph: the X-axis will be word
position and the Y-axis will be % recall.
 Do you see a pattern? Does is look anything at all like this
figure?:
Now you are going to analyze the results of your memory study.
 You
should have found that words read
first and words read last are remembered
better than words read in the middle!
WHY?
Can you explain why this
is in terms of short term
and long term memory??
Now or Later? The
“Recency/Primacy” Effect
 Explanation:
This experiment provides
evidence that there are 2 types of memory
(short term & long term).
 It is thought that memory is good for the
words read last because they are still in short
term memory (because you have just heard
them) - this is the Recency effect.
 And memory is good for the words read first
because they made it into long term memory
- this is the Primacy effect.
Research Methods Link
 Lab
experiments
4.To explain what a lab experiment is and
give advantages and disadvantages
 Capacity

How much can it hold?
 Encoding

How is information stored?
 Duration

How long does information last?
 Encoding:
info enters the brain via the senses and is
then stored in various forms. A stimulus can be
encoded visually as a word or picture, acoustically
(sound) or semantically- (knowledge about the
meaning of the word)
glove
Capacity and Encoding
Short Term Memory
Capacity
Chunking
Enoding
Click Here to Continue
We are finding out about…..
•
•
•
Capacity of STM
Chunking in STM
Encoding in STM
All this by participating in some simple experiments.
Click on the forward button to proceed.
Experiment 1- Capacity of
STMBefore proceeding, you will need a pen/pencil and a
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
sheet of paper.
When you go to the next page, you will be presented with
a sequence of numbers, which will appear in the centre of
the screen at one second intervals.
Try to memorise the numbers in sequence as they are
presented.
When you hear a tone/see the word NOW appear, write
the numbers down in the same order as they were
presented, (serial recall), on the sheet of paper.
Click on the forward button to start Trial 1 of Experiment 1.
3
5
7
4
6
8
9
2
1
NOW
How did you do?
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574831962
- see below
Miller, (1956) talks of ‘the magical number seven, plus or minus
two’, meaning that:
on average, the capacity of STM is between 5 and 9 items of
information.
Try the experiment again, this time with letters as the stimulus
material, writing them down in the same order as they were
presented, when you see the word NOW appear.
You will need a fresh sheet of paper.
Click on the forward button to start Trial 2 of Experiment 1.
Q
E
S
A
R
B
H
K
T
NOW
Difficult, isn’t it? - Answers below
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QAHERSBKT
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You probably found that you remembered
between 5 and 9 items, digits or letters, on each
trial, in line with Miller’s (1954) findings.

Now try Experiment 2 - click on the forward button
for details.
Experiment 2
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Before proceeding, you will need a pen/pencil
and a fresh sheet of paper.
When you go to the next page, you will be
presented with a line of letters across the centre of
the screen which will appear for approximately 10
seconds.
Your task is to remember as many of the letters as
you can, in the order in which they were
presented.
When you see the word NOW appear on the
screen, write down on your paper as many of the
letters as you can remember, in the same order as
they were presented.
Click on the forward button to start Trial 1 of
Experiment 2.
GCEBTECGCSEGNVQAS
NOW
Difficult, wasn’t it?

Now try it again, using a fresh sheet of paper,
obviously!

Click on the forward button to start Trial 2 of
Experiment 2.
GCE BTEC GCSE GNVQ AS
NOW
You probably did better this time - Answers below.
GCE BTEC GCSE GNVQ AS
Why might this be? – (apart from having seen the stimulus
material twice, an example of the practice effect).
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Miller (56) found that the capacity of STM could be
considerably increased by combining, or organising,
separate ‘bits’ of information, e.g. letters or digits, into
larger chunks.
Armed with your new-found knowledge, click on the
forward button to try Trial 3 of Experiment 2, writing your
answers on a fresh sheet of paper when the word NOW
appears.
190019141918193919452000
NOW
How did you do this time?
Answers below
 190019141918193919452
000

1
2
Based on existing knowledge of the two World
Wars of the 20th century, you might have been
able to reorganise these 24 bits of information into
2 CHUNKS, i.e.:
The dates of the two World Wars, 1914-1918 and
1939-1945;
the beginning and end of the 20th century, 1900
and 2000.
Experiment 3 - Encoding in
STM
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As before, you will need a pen/pencil and a fresh
sheet of paper.
When you go to the next page, you will be
presented with a sequence of letters, which will
appear in the centre of the screen at one second
intervals.
Try to memorise the letters in sequence as they are
presented.
When you hear a tone/see the word NOW
appear, write the letters down in the same order
as they were presented, (serial recall), on the
sheet of paper.
B
C
V
G
E
D
P
T
NOW
How many did you get? - answers
below.
BDTGCPEV
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Remember, to count as correct, the letters must
be in the correct sequence.

Armed with a fresh sheet of paper, click on the
forward button to start Trial 2 of Experiment 3.
W
Q
A
F
M
L
R
Z
NOW
How did you do this time?
- answers
below
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WLFZMQRA
You probably did better on trial 2, above. This is in
line with previous research which has found that
sequences of letters, (Conrad, 1964), or words,
(Baddeley, 1966), which are acoustically similar,
i.e. sound similar, are harder to recall from STM
than sequences which are acoustically dissimilar.
Such acoustic confusion errors suggest that STM for
such material mainly relies on a speech-based or
acoustic code, even though the items were
presented visually.
Conrad concluded that items are stored in STM as
an acoustic code
Short Term Memory
Duration
How long can you retain a new phone number before
you have to write it down?
…if you didn’t rehearse it?
 The
duration for which STM can retain info is
temporary – a very short time
 Not
much research interest of this aspect, but…
 …some
findings suggest only a few seconds
before it fades/decays (unless we rehearse it)
Activity: duration of STM
 This
next experiment was first carried out by
married couple Peterson & Peterson (1959)
 Got students to recall combinations of 3 letters
(trigrams), after longer and longer intervals.
 During the intervals, students were prevented
from rehearsing by a counting task!
 On the next screen, you will see a trigram for a
few seconds.
 A 3-digit number will then appear in its place.
When this happens, start counting backwards in
3’s from the number until you are told to stop.
 Pens down….ready?
303
V J
P
X G A
419
K
297Z Y
 Their
findings suggest that our STM fades in under
a half a minute if we are not rehearsing it:
After 18secs, fewer
than 10% recalled
correctly.
After only 3secs,
80% recalled
correctly.
Recall got progressively
worse as the delay
grew longer!
The Nature of Short and Long Term
Memory
Peterson and Peterson (1959)
Investigated the duration of STM, preventing
rehearsal
Findings:
3 second interval (condition 1) – more words
recalled
18 second interval (condition 6) – less recalled
Conclusion:
Information stays in STM for less than 18 secs if
verbal rehearsal is prevented. Most actually
disappears in the first few seconds.
 Capacity

How much can it hold?
 Encoding

How is information stored?
 Duration

How long does information last?
 Capacity
Our LTM is so big it is
to measure
 impossible
How much
can itsohold?
it can hold and
UNLIMITED amount of
 Encoding
information

How is information stored?
 Duration

How
long
information
last?
They can
lastdoes
a life time
so
it depends how long you
live!
LTM- Capacity
 Seems
to be limitless- so why do we forget
things?
 Memories
last a long time, however we
are not always able to retrieve the info.
 Evidence-
the ‘tip of the tongue’
phenomena
Encoding
Storage
Retrieval
LTM- Duration- Lasts a
lifetime?
Bahrick at al (1975)
 Natural experiment 400 ppts aged 17-74
asked to list high school classmates,
names, recognise classmates photos,
recognise classmates names.
LTM- Duration- Lasts a
lifetime?
Bahrick at al (1975)
Results
 Test < 15 years since school
recognition was 90% accurate for
names and photos



Test = 48 years later, 80% names,
70% photos!
Free recall- less good
◦
◦
15 years- 60%
48 years 30%
LTM- Duration- Lasts a
lifetime?
 Bahrick
at al (1975)
 Conclusions
 Our
memories can last a long time.
 Recognition is better than recall- suggests
memories are there but we can’t access
them.
The Long
Term Memory
Encoding
Activity: encoding in LTM

Try to memorise them in order, and wait for
the word “NOW!” before you write…
NOW!
DREAM
YAWN
SLEEP
SLUMBER
DOZE
NAP
REST
SNORE
KIP
SNOOZE
Now write down as many as you
can remember.
You should have done ok, as you were using your STM
 Based on Baddeley (1966)
 Presented lists of 10 short words one at a time
 Some lists were semantically similar, others not
 Tested immediately & then after 20 min delay
 Found that after 20 mins, they did poorly on the
semantically similar words
 This suggests that we encode LTMs according to
what they mean – so we get similar-meaning things
confused!
 Encoding in LTM is “semantic” – meaning-based
Baddeley (1966)
 Participants
were given four sets of words to recall in
order. For the STM task they had to recall them
immediately following presentation and for the LTM
task they had to be recalled following a longer time
interval.
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
Set 1 were words that all sounded similar, for example: cat, mat, cap,
map…
Set 2 were words that sounded differently for example: dog, bin, cup,
pen….
Set 3 were words of similar meaning for example: big, large, huge,
vast…
Set 4 were words of different meaning for example: huge, good,
light, blue….
The researchers then recorded the how many mistakes were made in
recalling the sets of words.
Findings
 STM- In the STM procedure participants made significantly
more mistakes on words that sounded alike so for example
would confuse cat and cap etc. Similarly with letters, S and X
would be confused as would M and N and P and B etc.
 Conclusion- It was concluded that in STM information is
encoded by its sound (acoustically) so when we recall
information from STM similar sounding words get confused.
 LTM In the LTM procedure participants were far more
likely to confuse words of similar meaning replacing
huge with vast or night and dark etc.
 Conclusion- It was concluded that in LTM information is
encoded by its meaning (semantically).

Can you distinguish between
STM and LTM?
Look back at what you have learnt today
so far.
Use the table provided to produce a
summary of the differences between STM
and LTM
Include the research studies
Plenary Activity (Include studies)
Definition
STM
LTM
Capacity
Encoding
Duration
The Nature of Short and Long Term
Memory
1.
STM and LTM differ in 3 important ways
DURATION
STM – very limited (<20 secs)
LTM - potentially unlimited (a persons’ lifetime)
2.
CAPACITY - How much can be held in memory.
STM – limited (7 +/- 2 chunks)
LTM- potentially unlimited capacity
1.
ENCODING
STM- mainly encoded acoustically (sound)
LTM – mainly encoded semantically (meaning)
Research Methods Link
 Lab



experiments
Conducted in a special environment where
variables can be carefully controlled.
Participants are aware that they are taking part in
an experiment.
They may or may not know the true aims of the
experiment. (Is this ethical?)
To explain what a lab experiment is and
give advantages and disadvantages
Strengths and weaknesses of Lab
Experiments
Artificial or contrived.
 Participants know they are
being studied, which is likely
to affect their behaviour.
 Investigator may influence
results.
 The setting is not like real life
– low in mundane realism.
 Because IV and DV have
been operationalised it
doesn’t represent real-life
experiences e.g. trigrams to
test memory
 Low ecological validity

Well controlled.
 Permits us to study
cause and effect.
 Confounding variables
minimised.
 Can be replicated
(copied/repeated)

Ethical Issues
Deception
Informed consent (is it truly
voluntary?)
Psychological harm
Tasks
Complete the key study sheets on each of
the experiments covered today.
Have a go at evaluating them!
Finish for homework
How will I know if I am learning?
1.Describe STM in terms of capacity, encoding and
duration (AO1)
2.Describe LTM in terms of capacity, encoding and
duration (AO1)
3. To provide evidence in the form of studies for each
description. (AO2)
4.To explain what a lab experiment is and give
advantages and disadvantages (AO3)