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MEMORY
Unit 4 Psychology
RAH
INTRODUCTION
Without memory, every moment would be a new
experience.
 You would have no self-concept or personal
identity, e.g. “Who am I?”
 Memory provides meaning to our lives by
integrating the past, the present and enabling us
to think about the future.
 Memory consists of a collection of complex
interconnected systems, each of which serves a
different purpose and operates in a very different
way.
 We do not have a memory – we have different
memory systems.

INTRO CONT…

Memory systems have
some functions in
common:
Receive
 Process
 Store info for future use
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Human memory is not
perfect.
Perceptual systems are
constantly bombarded
with stimuli during our
waking lives.
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The brain must select
what information will be
attended to, processed
and stored in various
memory systems.
It must also decide what
will be eliminated and
therefore not stored in
memory.
This process is
necessary or our
systems would be
overloaded.
MEMORY AS AN INFORMATION
PROCESSING SYSTEM
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Most psychologists view
memory as an active
information-processing
system that receives,
organises, stores and
recovers information.
Comparable to how a
computer processes
information.
Like a computer, memory
does not passively receive
and store new information.
Instead, it actively alters
and organises incoming
information so that it can
be stored in a way that is
relatively easily retrieved.

Computers and human
memory are also
comparable because they
each deal with information
in a sequence involving
three key processes:
The encoding of
information into a useable
form
 Its storage or retention
after being encoded
 Its retrieval or recovery
when needed.

ENCODING
Information that is
received and stored in
memory must be
converted from its raw
sensory state to a
form that the brain
can process and use.
 New info must be
placed or represented
in some form (sound,
visual etc) in the
memory system.

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The entire process of
CONVERTING
information into a
useable form or code
that can be stored in
memory is called
encoding.
STORAGE
Next, info must be
retained (kept) by the
IPS.
 Storage is the
retention of
information over time.
 Human memory
stores info in the
brain.

RETRIEVAL

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Lastly, info is retrieved
and taken out of
storage, when it is
needed.
Retrieval is the process
of locating and
recovering the stored
information from
memory so that we are
consciously aware of it.

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Some info is easy to
retrieve, e.g. birth date.
Other info is harder to
retrieve and we rely on
cues to retrieve
information that has
been stored in memory.
When human memory
works effectively,
encoding leads to
storage and storage
enables retrieval.
ENCODING, STORAGE AND RETRIEVAL
Incoming
sensory
information
Encoding
Storage
Retrieval
Information
is converted
for storage
Information
is retained
in memory
Information
is recovered
from
memory
when needed
*If any one of these processes fail, information will not be
remembered.
MEASURES OF RETENTION
How can you find out whether information has
been retained in memory?
 Research findings suggest that the amount of
information that will be retrieved from memory
is, at least partly, dependent on the type of
retrieval questions asked.
 3 main kinds of measures used to determine how
much information has been retained: recall,
recognition and relearning.

RECALL
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Recall involves being
asked to reproduce
information with the
fewest possible cues to
assist retrieval.
Free recall is involved
when participants are
simply asked to
remember as much
information as they can,
in no particular order.
Serial recall is being ask
to remember
information in the order
you learned it.
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During recall, you use a
general cue to retrieve
info, however, it does
not always provide
enough of a hint for you.
Therefore, the more
specific the cue, the
more likely you are to
locate and retrieve the
relevant, correct
information stored in
you long term memory.
Cued recall makes use
of more specific cues to
aid retrieval.
RECOGNITION
Recognition involves
indentifying the
correct information
from among
alternatives.
 We generally retrieve
more information with
this method, as we are
provided with more
cues or prompts.
 You can typically
recognise more than
you can recall.

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E.g.
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Multiple choice
True/false
A list of alternatives is
provided.
RELEARNING
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Relearning (method of
savings), involves learning
info again that has been
previously learned and
stored in long-term
memory.
If info is learned more
quickly the 2nd time, it’s
assumed that there must
be some info retained from
the 1st learning experience.
Learning is considered the
most sensitive of the 3
measures of retention.
Relearning takes less
time than it did
originally to learn.
 It’s also called method
of savings as it can be
used to measure the
amount of info ‘saved’
from previous
learning.

SAVINGS ARE CALCULATED BY:
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Savings = (no. of trials for original learning) – (no. of trials for relearning)
(no. of trials for original learning)

x 100
1
A savings score can also be calculated on the basis of the
time taken to relearn information.
(time for original learning) – (time for relearning) x 100
(time for original learning)
1
HERMAN EBBINGHAUS
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German psychologist,
Ebbinghaus (1885) was the
1st researcher to
scientifically study
relearning.
He memorised nonsense
syllables such as jax, qir
and kuv.
These syllables are used in
memory research instead
of words so retention is not
affected by the words
having some sort of
meaning with others words
already in memory.
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Ebbinghaus found that
even if he could not
remember a single item
from the original list, he
could relearn the list much
more quickly a 2nd time
than he had learned it
originally.
He assumed that some info
had been retained from the
initial learning.
Nonsense syllables consist of 2
consonants and 1 vowel in
between. They are
pronounceable, but have no
meaning.
RELATIVE SENSITIVITY OF MEASURES OF
RETENTION
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The sensitivity of a
measure of retention refers
to its ability to assess the
amount of info that has
been stored in memory.
Evidence indicates that:
 Recall is least sensitive
 Relearning most
sensitive
 Recognition in between

Read through
experiment on page
335 of textbook.
STAGES OF MEMORY
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The Information Processing Approach to memory has 2 key
features:
1. that mental processes such as memory can be best
understood by comparing them with the workings of a
computer.
2. that memory processes can be explained in terms of info
progressing through a series of separate stages, one step at
a time, but not necessarily in one directions.
The information processing model of memory proposed by
Richard Atkinson & Richard Shiffrin (1968), sometimes
called the modal model or the stage model for memory,
provides a broad framework that is useful in explaining the
basic workings of memory.
THE ATKINSON-SHIFFRIN MODEL
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Describes human memory
as consisting of 3
distinguishable kinds of
memory. Each 1
representing a stage
through which info passes
in a sequential way.
When info is received from
the environment, it passes
from sensory memory to
short-term memory and
then to long-term memory.
Info may also pass back
from long-term memory to
short-term memroy.

Each stage differs in
terms of its function,
its capacity and its
duration.
SENSORY MEMORY
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All information, whether
you pay attention to it or
not, is temporarily held in
sensory memory.
Sensory memory is the
entry point for new
information into the
memory system.
Info is not encoded
SM has the capacity to
store all sensory
experiences (briefly) &
therefore it is assumed to
be unlimited in capacity.
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Stores sensory impressions
long enough so that they
over lap. Thus world is
perceived as continuous.
We attend to and select
the info to be transferred
to short term memory
(STM).
If sensory info is not
attended to and nor
further processing
(encoding) occurs, it fades
& cannot be transferred to
STM.
ICONIC MEMORY
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Incoming sensory info is
stored in separate subsystems called sensory
registers.
Iconic memory is the name
given to visual sensory
memory, or the memory of
visual sensory info.
Each new image is
registered in iconic
memory before the
previous image fades,
hence you are able to ‘see’
the entire image.

Close your eyes for one
minute. Near the end
of the minute, hold
your hand about 25
centimetres in front of
your eyes. Then open
you eyes and rapidly
close them again.
What do you see?
GEORGE SPERLING (1960)
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Demonstrated existence of
a sensory register for
visual sensory information.
He used a tachistoscope to
present participants with
sets of 12 letters arranged
in a pattern and
participants had to write
down as many as they
could recall.
Most could recall only 4 or
5.
In such short exposure
only , reporting all letters
was impossible.
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Participants reported they
remembered seeing the letters,
but by the time they had to write
them, they had faded from
memory.
So to test that all letter remained
in iconic memory, he conducted a
further experiment in which he
sounded a tone just after a
pattern of letters.
Each tone had to do with a row &
participants were able to better
recall the letters.
Results indicate that an image of
all the letters had been
momentarily stored in the iconic
memory after pattern left the
screen.
ECHOIC MEMORY
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Echoic memory is the
name given to auditory
sensory memory, because
sounds linger like an echo.
Processes all kinds of
sounds.
It stores sounds in their
original sensory form.
The main difference
between iconic & echoic
memory seems to be the
length of time it takes info
to fade.
Echoic stores for typically
3-4 seconds and iconic for
0.3 seconds (approx.)
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Echoic memory stores the
tail-end of the question
temporarily while earlier
parts of the message are
being processed.
This is important for
understanding speech.
Auditory info must be
stored long enough for all
the sounds involved to be
received.
SENSORY MEMORY CONCLUSION
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SM can store virtually all
the info provided by our
sensory receptors, yet, this
info fades rapidly.
It happens so quickly that
that we are rarely aware of
our capability for storing
sensory info.
SM may act as a filter to
keep out irrelevant and
unimportant info and
prevent it from cluttering
the sensory stores.
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When you attend to info in
sensory memory, it is
transferred to short-term
memory.
Only the info selected for
transfer to short-term
memory receives further
processing and has a
chance of being stored
permanently.
Info that is not attended to
in SM is lost very quickly.
SHORT-TERM MEMORY
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STM is a memory system
with a limited storage
capacity in which info is
stored for a relatively short
period of time (but longer
than sensory memory).
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The info is an
encoding(representation).
Items in STM can be retained
for the 1st few seconds.
After approx 12 seconds,
recall starts to decline and by
about 18 seconds almost all of
the info disappears entirely if
it is not renewed in some way.

Generally, most info is lost
from STM after 20
seconds.
Info can be reviewed and
this retained in STM for
longer periods of time
through use or by
consciously repeating it.
STM temporarily holds all
the info you are
consciously thinking about
at any moment of time.
STM AS WORKING MEMORY
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Also known as working
memory.
Working memory is an active
part of memory where info
you are consciously aware of
is actively ‘worked on’,
thought about and processed.
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It works on info from sensory
memory and long term
memory (LTM).
Imagining, problem solving,
analysing, reasoning,
comprehending and planning
all involve working memory.
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When you mentally add the
numbers 17+5+12, the info is
temporarily held in working
memory while it is being used
or worked on.
Thus working memory
provides a temporary storage
facility and ‘mental
workspace’ for info currently
being used in some conscious,
cognitive activity.
Once info has been used, it is
either further processed and
moved to LTM or discarded.
ALLAN BADDELEY (1999)
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Proposed that working
memory consists of 3 subsystems:
 1. verbal info
 2. visual info
 3. a ‘central executive’
that does the work of
processing info in the
other 2 sub-systems.
Verbal working memory
(or phonological loop)
stores a limited number of
sounds for short period of
time.
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Visual working memory (or
visuospatial sketchpad)
temporarily stores visual and
spatial info, such as location.
The central executive
integrates info from the
verbal and visual storage
systems, as well as info
retrieved from LTM.
It’s also responsible for
suppressing irrelevant info
from our conscious thinking.
The central executive plans &
coordinates, but most
psychologists believe it does
not store info.
ALLAN BADDELEY’S (1999) MODEL OF
WORKING MEMORY
Sensory
Memory
Working
memory (STM)
Phonological
Loop
Visuo-spatial
sketch pad
Central
Executive
Long Term Memory
DURATION OF STM
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Info can be kept in STM
for longer than the usual
maximum of about 18-20
seconds by maintenance
rehearsal.
Psychologists Margaret &
Lloyd Peterson (1959)
conducted an experiment
where participants were
given trigrams to
memorise.
Participants where then
given an interference task
to prevent rehearsal of the
trigrams.
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Following a time interval
that varied from 3-18
seconds, a light was used
as a signal for participants
to recall the trigrams.
The longer the interval,
the less likely a
participant was to
accurately recall a trigram.
CAPACITY OF STM
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STM is very limited in
storage capacity.
George Miller (1956)
researched that STM has a
capacity of holding
between 5 & 9 units of info
at any one time (published
‘The magical number 7,
plus or minus 2’).
Estimates are obtained by
asking research
participants to memorise
simple lists of data of
different lengths.
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The length of the list that
the participants can recall
half the time is considered
to represent the capacity of
STM.
When STM is ‘full’, new
items can only be added by
pushing old items outs.
Space in STM is also filled
when we think and when
information is temporarily
brought from LTM into
working memory to be
used or updated.
CAPACITY OF STM: DECAY &
DISPLACEMENT
Info stored in STM is
lost primarily through
decay & displacement.
 Decay of info (not
being used) in STM
occurs when you
forget what you want
to say in a
conversation while
you wait for the other
person to finish
speaking.
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Displacement of info (being
pushed out) from STM was
demonstrated in research
in which participants
called directory assistance
for a long-distance
telephone number.
They showed poorer recall
of the number if the person
providing the info said
‘have a nice day’ after
giving the number.
Complete activities on page 347.
ACTIVITY

Read the sequence of letters below:

D N V R C E W V DC S V
Now close your eyes and try to repeat the letters
aloud in the same order.
 Unless you have an exceptional STM, you
probably could not repeat the whole sequence
correctly. Now try this sequence of letters:


NSW VCR VCE DVD
Is it easier to remember than the first sequence?
 The increased ability to recall the second
sequence demonstrates chunking.
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CHUNKING INFORMATION
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Chunking is the grouping
or ‘packing’ of separate
bits of info into a larger
single unit or ‘chunk’ of
info.
Chunking can increase the
amount of info held in
STM.
STM is a working memory
system with limited
capacity and duration in
which info is lost rapidly
unless rehearsed.
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The capacity of STM is about
7 chunks of info, but this
amount can be increased by
increasing the amount of info
in each chunk.
However, not matter how
good a job we do of chunking
and rehearsing, info must be
transferred to LTM for more
permanent storage.
Thus, STM is used to work on
new info or info retrieved
from LTM, to select & process
ongoing info & to store
memories for a short
duration.
EFFECTS OF REHEARSAL
Info can be kept in
STM for longer than
the usual maximum of
about 20 seconds if it
is rehearsed in some
way.
 In the study of
memory, rehearsal is
the process of actively
manipulating info so
that it can be retained
in memory.
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There are 2 main
types of rehearsal –
maintenance
rehearsal and
elaborative rehearsal.
MAINTENANCE REHEARSAL
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Involves repeating the info
being remembered over
and over again to retain it
in STM.
It can be verbal (words)
and non-verbal (visual).
When it’s verbal,
maintenance rehearsal can
occur vocally or subvocally.
Maintenance rehearsal
does not always lead to
long-term retention.

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Nonetheless, maintenance
rehearsal is an important
technique for coping with
the limited during of STM.
One drawback however is
that when info is
continually renewed in
STM through rehearsal
processes, the amount of
new info that can enter is
restricted because of the
limited storage capacity of
STM.
ELABORATIVE REHEARSAL
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While maintenance
rehearsal is an effective
strategy for retaining
information in STM, it
does not assist in encoding
info for transfer to LTM.
Elaborative rehearsal is
the process of linking new
info in a meaningful way
with info already stored in
memory or with other new
info, to aid in its storage
and retrieval from LTM.

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Elaborative rehearsal is a
more active process than
maintenance rehearsal. It
is also more effective than
maintenance rehearsal for
remembering info because
it helps to ensure that info
is encoded well.
When we relate new info to
personal experiences and
our personal situation,
encoding is enhanced and
therefore we are more
likely to remember it. This
is called the self-reference
effect.
CONSOLIDATION THEORY
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Proposes that physical
changes to the neurons in
the brain occur when
something new is being
learned, and immediately
following learning.
These neuronal changes
occur for a period of time
after learning takes place,
as the new info
consolidates in memory.

Also proposes that if
memory is disrupted
during the consolidation
phase, info may be lost &
not processed into LTM.