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 Take
a minute to list all the things that our
memory is useful for.
 Now
think about all the things that we
wouldn’t be able to do if we did not have our
memory.
-tying shoelaces
-remembering faces
-no friends
-no self-concept
-no personal identity
 Human
memory is not a single organ.
 Technically
we do not actually have a
memory- we have different memory
systems.
 Memory
consists of a collection of
complex interconnected systems, each
of which serves a different purpose
and operates in a very different way.
 Despite
these differences, all memory
systems have some functions in commonthey each receive, process and store
information for future use.
 When
we receive sensory information the
brain must select what information will be:
a) attended to, processed and stored in the
various memory systems
b) eliminated and therefore not stored in
memory.


If this process did not occur our memory
systems would be overloaded with
unimportant information.
Eg. The case study of ‘S’.
 In
terms of people who are said to have “lost”
their memory- this is generally a reference to a
situation where one or more memory systems
have malfunctioned.
 To
have no memory at all you would probably be
unconscious or dead.
Because memory is so closely related to
learning it can be defined as the
storage and retrieval of information
acquired through learning.
Most psychologists view memory as an
active information-processing system
that receives, organises, stores and
recovers information similar to the way
a computer operates.
 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.
 Memory
and a computer are also comparable
in the way that they each deal with
information in a sequence involving three key
processes: encoding, or conversion of
information into a useable form; its storage or
retention after being encoded; and its
recovery or retrieval when needed.
 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 information must also be placed, or
represented, in some form- sound, visual
image, touch or meaning- in the memory
system.
 The entire process of converting information
into a useable form or code that can be
stored in memory is called encoding.
 Similar to transduction in visual
perception.
 Next,
information must be retained by the
information-processing system.
 Storage
is the retention of information over
time.
 Personal
computers usually store information
on a hard drive, whereas human memory
stores information in the brain.
 Finally,
the information is retrieved, or
located 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.
 The
retrieval of some information is very easy
and quick, such as your name or birth date.
 Other
information is harder to retrieve such as
something you learnt in year 7 science.
 In
these instances we often rely on cues to
retrieve information that has been stored in
memory.
 Many
models have been presented in trying
to explain how memory works as a structure
or construct that we rely on so much.
 Some
models have been more influential
than others and continue to be studied and
revisited by researchers to improve our
understanding of memory.
 Three
-
-
-
models that we will study are:
Atkinson and Shiffrin’s (1968) multi-store
model which describes memory as having
three components called the sensory
register, the short term store and the long
term store
Baddeley and Hitch’s (1974) model of
working memory, which changes views on
the roles and functioning of short term
memory
Craik and Lockhart’s (1972) levels of
processing framework which emphasises the
importance of the ‘depth’ at which we
process information.

American Psychologists Richard Atkinson and
Richard Shiffrin developed the first influential
model of memory in 1968 called the multi-store
model.

The Atkinson-Shiffrin multi-store model
represents memory as consisting of three
distinguishable components called the sensory
register, the short-term store, and the long-term
store. Each component, or store, represents a
place where information is stored and processed.
 Although
these three memory systems are
viewed as separate sub-systems of memory,
they each operate simultaneously and interact
in many ways.
 Within
each stage of memory, information
processing involves encoding, storage and
retrieval of information.
 According
to this model, when information is
received from the environment, it passes from
the sensory register to the short-term store
and then to the long-term store.
 Each
stage of memory differs in terms of its
function (the role it plays), its capacity (the
amount of information it can hold at any given
moment) and its duration (the length of time
it can hold information).
 The
sensory store is the entry point for new
information into the memory system.
 It
stores vast quantities of information for a
very brief period of time (milliseconds)
 Anything
that is not attended to in sensory
memory is then lost.
 If
the information is attended to it is then
passed on to the short-term store.
 The
short term store is described as a
‘temporary working memory’ in which we
manipulate information that is held to perform
everyday functions.
 It holds the information that we are consciously
aware of at any given time.
 It receives information from the sensory register
as well as retrieving previously stored
information from your long term store.
 It has a limited capacity and can only hold
around 7 items of information at a time, and
only for around 30 seconds unless a conscious
effort is made to keep it there longer.
 This is achieved through rehearsal.
 The
long term store holds information relatively
permanently in a highly organised way and has
an essentially unlimited capacity.
 It does not usually decay and can be stored for a
lifetime.
 We can however find it difficult to retrieve
information if we use ineffective search
strategies or by failing to use the correct
memory trace.
 This can also be caused by interference.
 An
important feature of the model is its
description of memory in terms of it structural
features and its control processes.
 Structural features are the permanent, built-in,
fixed features of memory that do not vary from
one situation to another.
 Eg. The three different stores, the function of
each store, the capacity and duration of each
store.
 Control
processes are selected and used by
each individual and may vary across different
situations.
 They are under the ‘conscious’ control of the
individual and which process is used depends on
the particular person.
 Eg. Whether the individual attends to the
information, whether they rehearse the
information and the search strategies that they
use.
 Given
the time that has passed since the
evolution of the multi-store model,
psychologists have built on and reconsidered
many components of Atkinson and Shiffrin’s
work.
 This
lead to the study of the three memory
systems in more detail and their name changes
to sensory memory, short-term memory and
long-term memory.
 Sensory
memory is the entry point of
memory-the initial stage of the memory
system in which all of the stimuli that
bombard our senses are retained in their
original sensory form (not encoded) for a
very brief time.
 It
is assumed to be unlimited in capacity.

An important function of sensory memory is that it
stores sensory impressions long enough for them to
slightly overlap one another. (Waving a pen in
front of your face).

This means that we see the world as continuous
and not as a series of disconnected visual images
or sounds.

Sensory information remains in sensory memory
just long enough for it to be attended to and
selected to be transferred to short-term memory
(STM).

We are not consciously aware of the majority of
information that enters our sensory memory.

However when we direct our attention to it in
order to store it in STM we become consciously
aware of it.

Incoming sensory information is stored in separate
sub-systems called sensory registers and it is
believed that there is a separate sensory register
for each of the senses.

Iconic Memory is the name given to visual
sensory memory, or the memory of visual sensory
information.

Visual images in their original sensory form are
usually retained in iconic memory for one-third
of a second.

Sperling’s experiment.
 Used
a tachistoscope to briefly present 12
letters to participants.
 The participants were asked to verbally
report as many letters as they could recall.
 Most could recall only 4 or 5 but reported
seeing all of the letters for a brief second.
 He then extended his research into using a
tone to measure how long the image was
stored.

Some people are able to remember highly detailed
scenes as if the actual event were occurring before
them.

These people are said to have eidetic memory. These
memories are said to be an exact replica of a visual
image that persists over time without distortion.

These can last sometimes for days or weeks.

View this image for 30 seconds and then answer the
following questions.
1.
2.
3.
4.
5.
6.
How many bows are on the girls apron?
Is the hemline of the girl’s dress above or
below her knees?
How many flowers are in bloom on the taller
plant?
How many whiskers are there on the cat in
the tree?
How many stripes are on the cat’s tail?
What is the girl wearing in her hair?
 Echoic
Memory is the name given to auditory
sensory information, or the memory of auditory
sensory information.
 It
is called echoic memory because the sounds
linger in it like an echo.
 Echoic
memory stores information for longer
than iconic memory.
Iconic (visual)
Memory
About 0.2-0.4
seconds
Echoic (auditory)
Memory
About 3-4 seconds
 The
availability of this information for 3-4
seconds is generally long enough to select
what has been heard for further processing
and interpretation before the sound
disappears completely.
 Auditory
information must also be held for
long enough for all parts of speech within a
list of words to be identified.
 Short-term
memory (STM) is a memory
system with a limited storage capacity in
which information is stored for a
relatively short period of time (unless
renewed in some way).
 STM
stores information temporarily but
for a longer time than sensory memory.
 In
short term memory the information is
no longer an exact replica of the original
sensory stimulus, but an encoding of one.
 Generally
items in STM can be retained fairly
well for the first few seconds.
 After 12 seconds, recall begins to decline and
by about 18 seconds almost all of the
information disappears entirely if it has not
been renewed in some way.
 Information can be renewed in STM and
retained for longer through use or by
constantly repeating it.

Compared to sensory memory and long-term
memory, STM is very limited in storage capacity.

If you have an average storage capacity you should
be able to recall around seven numbers in a row. If
you were given eleven numbers this would not be
quite as easy.

The limited capacity of seven bits of information in
short-term memory was first described by George
Miller in 1956.
 http://faculty.washington.edu/chudler/stm0
.html
 Millers
research indicated that STM has a
capacity of holding between five and nine
units of information at any one time.
7
+2
 Rarely
are we able to hold any more than 7
+ 2 pieces of information in STM regardless
of what type of information it is.
 Information
stored in STM is lost primarily
through decay (not being used) and
displacement (being pushed out) by new
information.
 Many
psychologists prefer to use the term
working memory rather than STM.
 Working
memory is the active part of
memory where information you are
consciously aware of is actively ‘worked’ on.

Working memory works on information from sensory
memory and LTM.

Information from sensory memory is processed in
working memory and information is extracted from
LTM to be used and manipulated in working memory.
Imagining
- Problem-solving
- Analysing
- Reasoning
- Comprehending
- Planning
all involve working memory.
-
 Your
working memory enables you to read by
holding words from the beginning of a sentence
while you continue to process the rest of the
sentence.
 If
you were to work out a maths problem in your
head you would be using working memory.

We can get around the limited capacity of shortterm memory.

One way is to learn the information well enough
to transfer it to long term memory, which has an
unlimited storage capacity.

Another way is to put more information into
each of the 7 + 2 units that can be stored in STM.
DNVRCEWVDCSV
NSW
VCR
VCE
DVD

People are usually able to recall more of the
second set of letters even though it is made up of
exactly the same letters.

This is a demonstration of chunking.

Chunking is the grouping or packing of separate
bits of information into a larger single unit or
‘chunk’ of information.
Chunks can be take many forms. They can be
numbers, images, words, sentences, phrases or
abbreviations. (BHP, RACV, CSIRO).
 Phone numbers
 Car registration number plates


Rehearsal is the process of actively manipulating
information so that it can be retained in
memory.

There are two types of rehearsal:
-
Maintenance rehearsal
Elaborative rehearsal
-

Maintenance rehearsal involves repeating the
information being remembered over and over again
to retain it in short term memory.

When you hear something for the first time and go
over it and over it so that you don’t forget it, you
are using maintenance rehearsal.

Maintenance rehearsal can be verbal, which involves
the use of words. It can also be non-verbal, involving
visual or spatial information.

When the information is verbal, maintenance
rehearsal can occur vocally, by saying the
information aloud over and over; or sub-vocally, by
silently repeating the information in your head.

Whether maintenance rehearsal is verbal, visual or
spatial, provided it is not interrupted, information
can be retained indefinitely in STM.

This does not necessarily mean that this
information will automatically be transferred into
LTM.

When information is continually renewed in STM
through the rehearsal process, the amount of new
information that can enter is restricted because of
the limited capacity of STM.

Elaborative rehearsal generally involves
organising and dealing with new information in
terms of its meaning.

Elaborative rehearsal is the process of linking
new information in a meaningful way with
information already stored in memory or with
other new information, to aid in its storage and
retrieval from long term memory.

Elaborative rehearsal is a more active process than
maintenance rehearsal.

It is also more effective than maintenance rehearsal
as it helps to ensure that information is encoded
well.

When we relate new information 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.
Elaborative rehearsal has a number of practical
applications for students. The learning of new information
is more likely to be retained in LTM when you:
 Think about what the new information means
 Ask questions about the new information
 Link new information to previously learned information
 Create visual images relevant to the new information
 Link the new information to personal experiences or your
personal situation.

 In
1974 British psychologists Allan Baddeley
and Graham Hitch developed a multicomponent model of memory.
 Baddeley and Hitch’s model of working
memory describes the structure and function
of working memory in terms of three
components called the phonological loop,
the visuo-spatial sketchpad and the central
executive.
 The three components are separate and can
function independently but also interact.
 Baddeley
and Hitch were interested in studying
working memory as a system that supports and
enables complex and important cognitive abilities
which they felt it had not yet been considered as.
 Baddeley and Hitch proposed that memory
consisted of:
- One system for verbal memory
- Another for visual information
- And a central executive that processes the
information from the other two sub-systems.
 Think
of your house. How many doors does it
have in it?
 In working this out, you probably formed some
sort of visual image of your house. This relies on
the sub-system specialised for visual and spatial
information. You probably then counted the
doors verbally using the sub-system specialised
for verbal information. Finally, throughout this
process there was a need for your central
executive to select the strategy to complete the
task, to manage the activities of the other two
sub-systems and to control the whole process.
Verbal working memory (also called phonological
loop) stores a limited number of sounds
(phonemes), such as words, for a short period of
time.
 It encodes and stores auditory information and is
active whenever you read, listen, speak or repeat
words to yourself in order to remember them.
 Our use of internal, unspoken speech during
rehearsal is a crucial feature of the phonological
loop and verbal working memory.
 If we do not do this it becomes impossible to store
verbal information.
-
 Visual
working memory (also called the
visuospatial sketchpad) temporarily stores visual
information, such as the location and nature of
objects in the environment.
 Visual information is anything that you can see or
visualise, including features of the image.
 Spatial information refers to the location of
objects in space.
 If you closed your eyes to visualise what the room
looks like you would be relying on the visuo-spatial
sketchpad.
 Eg.
Imagine a 4x4 grid in your head (16 squares).
Next imagine the number 1 in the square that is in
the second column of the second row. Then put a
two to the right of that. Then, in the square above
the two, put a 3, and to the right of that put a 4,
Below the 4, put a 5, and below that a 6, and then
to the left of that a 7.
 What number is immediately above the 7?
 To answer this you had to use your visuo-spatial
sketchpad.
 The
central executive controls attention;
integrates information from the verbal and visual
storage systems, as well as information received
from long-term memory; and coordinates the flow
of information between the working memory and
LTM.
 It works on the information from the other two subsystems.
 This makes it the working part of working memory.
 The
central executive has a role in:
- Directing your attention to activities you are
currently undertaking
- Filters essential from non-essential information
- Combines information from the other two
components
- Selects, deletes and reorders information
- Adds information when required from LTM to guide
mental processes and behaviour.
Does not store information.
 According
to Baddeley a major problem with the
theory he developed with Hitch is that it does not
explain how working memory links with LTM.
 In 2000 Baddeley added a fourth component called
the episodic buffer.
 The episodic buffer is a sub-system of working
memory that enables the different components of
working memory to interact with LTM.
 The
episodic buffer is assumed to be a
limited-capacity temporary storage system
that holds about 4 chunks of information.
 It can hold any type of information and
therefore works to integrate information
from the other storage systems.
 The episodic buffer is directly linked to LTM
and it is separate and has its own storage
space and processes for storing information.
 It combines information into scenes or
‘episodes’ and allows them to be ‘buffed’ or
worked on.

Long-term memory is the relatively permanent
memory system that holds vast amounts of
information for a long period of time.

It is a different kind of memory system to STM
mostly because STM is active and LTM is inactive.

LTM differs from STM in several ways: how
information is retrieved, the form in which
information is stored and the way in which
information is forgotten.

LTM has to be organised in a way that enables the
efficient retrieval of information.

We retrieve information from LTM using retrieval
cues. This can be intentional or unintentional.

In either case, only the specific information relevant
to the cue is retrieved rather than the entire
contents of LTM.

Remarkably it takes only a few seconds to search
through this huge storehouse of information to find
the information required.

Information retrieved from LTM is held in working
memory while it is being used. Once it is no longer
required, it can be returned into LTM for further
storage.

If we are unable to retrieve specific information
from LTM, it is because of poor organisation of the
information during encoding and storage or failure to
use the appropriate retrieval cue.

If information is not properly stored it is difficult to
locate and retrieve.

STM stores information in terms of the physical
qualities of an experience, especially sounds.

In contrast, LTM stores information semantically,
that is in terms of its meaning.

In terms of forgetting, LTM differs from STM in that
it does not only last longer but it is in fact
permanent.

This means that forgetting occurs in LTM not because
the memory is gone, but because we are unable to
retrieve it.

Psychologists have distinguished between two
types of LTM storage, each with distinctly
different properties.

These are procedural memory and declarative
memory. Two types of declarative memory have
also been described. They are called episodic
memory and semantic memory.

Procedural memory is the memory of actions and
skills that have been learned previously and involves
knowing ‘how to do something’.
How to drive a car
 How to ride a bike
 How to use a computer

Procedural memories are also called implicit memories
because the information can be retrieved through
performance rather than intentional conscious recall
or recognition.
It can be difficult to put procedural memories into
words.

Declarative memory is the memory of specific facts
or events that can be brought consciously to mind
and explicitly stated or ‘declared’.

Consequently declarative memories are also called
explicit memories.
Identifying a type of flower
 Explaining a statistics formula
 Describing the events of a movie you have seen

 When
distinguishing between declarative and
procedural memory psychologists often refer
to declarative memory as involving ‘knowing
what’ and procedural memory as ‘knowing
how’.

Episodic memory is the declarative memory system
that holds information about specific events or
personal experiences.

Like a mental diary, recording the autobiographical
episodes we experience.
What you ate for breakfast
 The birth of a brother or sister
 Going to the dentist


Semantic memory is the declarative memory system
that stores the information that we have about the
world.

It includes our specialised knowledge in areas of
expertise, academic knowledge of the kind learned
in school, rules, everyday general knowledge, the
meaning of words.

Semantic memories seem to involve facts that do not
depend on a particular place or time but are simply
facts.
 It
could be argued that episodic and semantic
memories go hand in hand with each other in that
when we are storing a semantic memory we would
also have episodic memories being stored alongside
that.
 Fergus
Craik and Robert Lockhart were the
first influential psychologists to argue against
the concept that memory has a specific
structure that can be divided into sections.
 They proposed a conceptual framework of
memory which emphasized the importance of
the level at which new information is
processed.
 Craik
and Lockhart’s levels of processing
framework proposes that the level, or depth, at
which we process information during learning
determines how well it will be stored in LTM.
 They proposed that memories are best encoded,
organised and stored in LTM by meaning.
 However, processing meaning is not a matter of
meaning or no meaning.
 Instead there is a continuum ranging from shallow
to deep processing.
 Information
processed at the shallow level will
be held only briefly whereas information
processed at a deeper level will be held for
much longer.
 Elaborative (deep) vs maintenance (shallow)
rehearsal.
 Self-referencing involves deeper processing.
A
sample question from the research conducted:
1) required semantic processing
2) required acoustic processing
3) required visual processing
Which type of processing would be most effective?
1. Semantic
2. Acoustic
3. Visual
 One
problem with this theory is that the level of
depth is difficult to measure.
 It is accepted however, that deeper levels of
processing lead to more effective encoding and
therefore retrieval.

One of LTM’s most distinctive features is its
organisation of information. The task of retrieving
information from LTM is very different to retrieving
information from STM.

In STM there is only a choice of 7 + 2 pieces of
information to choose from, however LTM stores
such a vast amount of information that there is a
need for some form of information to assist the
storage and retrieval process.

Research has found that information stored in LTM is
organised in meaningful clusters of related
categories.

Eg. Fruit types, names, occupations.

Research findings also indicate that information is
also linked or associated with other information
stored in LTM.

There is also considerable research evidence that
suggests that recall from LTM is better when we
further organise the information stored there.

Bower and Clark experiment.

Information in LTM is both organised and associated
with other information held in the LTM system. The
semantic network theory is one theory that
describes how this is done.

Semantic network theory proposes that information
in LTM is organised systematically in the form of
overlapping networks or grids of concepts that are
interconnected and interrelated by meaningful links.

According to this model, each concept, called a node
is linked with a number of other nodes.

This means that when we retrieve information, the
activation of one node causes other related nodes to
be activated also.

In reality, LTM contains thousands of concepts, each
with very many connections.

This system of storing information in terms of
meaning is quite an effective means of storage
which enables effective and efficient retrieval of
information.
According to the semantic network theory:
 retrieval begins with someone searching a particular
region
 then tracing associations for links among memories
in that region, rather than randomly searching the
vast information stores in LTM.

It also proposes that a specific retrieval cue
activates relevant nodes, which in turn activate
other nodes to which they are linked.
 The
shorter the link between nodes the
stronger the association, the less time it
takes to activate related concepts to
which they are linked.
 The
longer the link between nodes the
weaker the association between them and
the longer it takes to activate the
information that is further away.
 The
more nodes that are activated, the
quicker the retrieval of information from
LTM.
 To
test whether STM is a separate sub-system of
memory from LTM, psychologists have studied
people’s memory of lists of words, numbers and
other information.
A
consistent finding has occurred: which words
are recalled from the list tends to depend on
their serial position in the list.
 The
Serial Position Effect is a research finding that
suggests that recall is better for items at the end
and beginning of the list than for items in the
middle of the list.
 The
Primacy Effect describes superior recall of
items at the beginning of a list.
 The
Recency Effect describes superior recall of
items at the end of a list.
 Together
with the relatively low recall of items
from the middle of the list, this pattern makes up
the serial position effect.
 The
most acceptable explanation relates to
differences between STM and LTM.
 If
recall occurs immediately after learning, the last
few items are remembered first because they are
still in STM.
 The
first few items are remembered most because
the received more attention and rehearsal than
other items and are therefore transferred into LTM.
 Items
around the middle of the list are
presented too late to be adequately rehearsed
and transferred into LTM and too early to be
held in STM without rehearsal and are therefore
likely to be forgotten.
 If participants are asked to recall the list 30
seconds after learning, the serial position effect
is not as prominent as this goes beyond the
limits of STM.
 This also works in real life settings such as with
advertisements.
 Memories
are not stored in any one location.
 They are stored throughout the brain and
linked together via neural tracts.
 This does not mean all areas of the brain are
equally involved.
 Different areas are active when we encode,
store and retrieve different types of
information.
 Most
relevant research conducted by Eric Richard
Kandel.
 He identified changes in the structure and
functioning of the neurons in the brain when
forming a new memory. He experimented on a
species of large sea slugs found in California called
Aplysia californica.
 He did this because these animals have a very
simple nervous system structure.
 They
also have some of the largest neurons in the
animal kingdom.
 This means they can be easily observed and
stimulated.
 Read experiment page 335.
 According to Kandel, when these animals acquire a
new memory through repeated stimulation,
significant changes occur in neurons involved in the
process.
 Draw neuron.
 The
more the neurons in a circuit are activated
through use, the easier it becomes for information
to travel through the circuit.
 In sum, Kandel’s research indicated that any
experience that results in memory produces
physical changes in the brain at the neuronal level,
strengthening connection between neurons and
making communication easier the next time.
 In
short term memories there is only an increase in
neurotransmitter.
 In long term memory all changes occur.
 Each time the memory is recalled the neurons in
this circuit are activated.
 Why
is the Kandel research difficult to generalise?
 Just
above the ear and about 4cm straight
into the brain is the hippocampus.
 The hippocampus is tubular and curved.
Humans have two, one in the temporal lobe
of each hemisphere.
 In 1957 a study highlighted the importance of
the hippocampus in memory.
 Ream HM’s story page 338.
 This
case highlighted the role of the
hippocampus in memory as:
- Being involved in the formation of new longterm memories, but not a storage site for longterm memories.
- Encoding new declarative (semantic and
episodic) memories but not really procedural
memories.
 Damage does not effect formation or retrieval
of procedural memories but does effect
declarative memories.
 Does not effect STM.
 Why
-
-
-
was HM able to remember old experiences
but not able to remember any new ones?
The hippocampus acts as a memory formation
area where the brain temporarily holds and
processes components of the information to be
remembered.
An episodic memory will have different
components which need to be integrated to
form a single memory.
When the memory is formed the different
components will transfer to the cortical areas of
the brain specialised in that component of the
memory (eg. Location- parietal lobe)
Consolidation theory proposes that physical changes
to the neurons in the brain occur when something
new is being learned, and immediately following
learning.
 These changes occur for a period of time after
learning takes place.
 This theory also proposes that if memory is disrupted
during the consolidation phase, information may not
be processed in LTM and will therefore be lost.
 If disruption does not occur the information becomes
a permanent part of LTM until it is retrieved.
 Consolidation is a gradual process and the material is
vulnerable to disruption for up to 30 minutes.

 It
is believed that the hippocampus and medial
temporal lobe in each lobe play an important role in
the consolidation process.
 In HM’s case it is suggested that he could not form
new LTM’s because the part of the brain used for
consolidation had been removed.
 Evidence comes from people who have experienced
brain trauma, been knocked unconscious, acquired
certain diseases, or received electroconvulsive
shock therapy.
 Other
research has come from animal research
involving rats.
 Administered ECT to rats at intervals of:
- Group A- immediately after running the maze (none
remembered)
- Group B- 20 seconds after (partial)
- Group C- 30 minutes later (partial but better than
B)
- Group D- 60 minutes after (complete recognition)
 It
has also been proposed that after a memory is
activated from LTM, it needs to be reconsolidated
to be stored back in LTM.
 This is called reconsolidation.
 This means that when we use an old memory we
can alter it, or adjust it with the new memories
formed before it is reconsolidated. This allows us to
build on the old memories.
 Many
causes of memory failure are caused by
damage or injury to the brain.
 The term brain trauma is an ‘umbrella’ term
that is used to refer to any brain damage
that impairs the normal functioning of the
brain, either temporarily or permanently.
 It could be inflicted (intentional blow or
seizure) or acquired (stroke or brain
disease).
A
neurodegenerative disease is a disease
characterised by a progressive decline in the
structure, activity and function of brain tissue.
 The neurons within the brain tissue gradually
become damaged and lose their function.
 This decline is usually age-related.
 Memory
loss due to any reason is called amnesia.
 The term amnesia is used to refer to loss of
memory, either partial or complete, temporary or
permanent.
 Any brain trauma typically results in amnesia.
 The severity of the injury determines the specific
characteristics of the amnesia.
 Often the period of lost memory will return over
time leaving only a small window unaccounted for.
 There
-
-
are many different kinds of amnesia,
each with a different pattern of symptoms.
Some examples are:
Amnesia for the meaning of nouns but not
verbs
Amnesia for animals and not people
Amnesia for human faces but not other
objects
Difficulty using STM or forming new LTM’s
Difficulty retrieving information from LTM
The two we will look at are anterograde
and retrograde amnesia.
 If
brain damage causes loss of memory only for
information or events experienced after the person
experiences brain damage, it is called anterograde
amnesia (A for after).
 In general any information from before the brain
injury remains.
 They are not able to remember what has happened
since the brain injury.
 Anterograde
amnesia is one of the symptoms
experienced by people with Alzheimer’s disease or
Korsakoff’s syndrome.
 Korsakoff’s
syndrome is a neurodegenerative
disease involving severe memory disorders
associated with damage to brain structures and
areas involved with memory, such as the
hippocampus and thalamus.
 This
disease occurs mostly in chronic or long-term
alcoholics.
 It is linked to the prolonged loss of vitamin B in the
diet and alcoholics often have this deficiency.
 Although this disease is considered to be
neurodegenerative symptoms can often appear in
just days.
 A person with this disease can appear quite normal
in terms of appearance, IQ, alertness, motivation
etc
 An
inability to remember information that was
acquired before brain damage is called retrograde
amnesia. (Retro refers to backward, and refers to
memory loss that goes back in time).
 The
extent of retrograde amnesia varies greatly,
ranging from moments to days, weeks or even
years.
 The
amount of time over which memories are
affected is often related to the severity of the
damage to the brain.
 In
most cases resulting from a brain injury, there is
some recovery of the lost memories- usually with
memory for older events recovering first.
 However,
there always seems to be a period –
usually just prior to the time when the brain injury
occurred- for which there is no recovery of memory,
and the amnesia is absolute.
 In
cases that are as a result of other damage to the
brain, such as Alzheimer’s disease, the extent of
the amnesia is often not clearly defined and the
recovery of the lost memories is rare.
 The
information processing model of memory
explains retrograde amnesia in terms of an
interruption to the consolidation of the memory
trace.
 In
the period of time just prior to the brain trauma,
a memory trace was forming as information was
being processed from STM to LTM.
 At
the point of the trauma, the consolidation
process was interrupted and therefore the memory
of information just prior to the injury will not be
consolidated and therefore lost forever.
 Dementia
is a general term that describes
the symptoms of a variety of brain illnesses
that progressively kill brain cells and result
in irreversible structural and chemical
changes in the brain that lead to permanent
and severe cognitive loss.
-
-
Loss of mental capacity
Memory loss
Decline in intellectual ability
Poor judgment
Poor social skills
Abnormal emotional reactions
 It
progresses in stages with memory loss being the
first sign and all symptoms worsen as ageing
progresses.
 In
the final stage people with dementia are
completely shut out of their world.
 The
most common form of dementia is Alzheimer’s
disease.
 Alzheimer’s
disease is a neurodegenerative
disease characterised by the gradual
widespread degeneration of brain neurons,
causing memory loss, a decline in cognitive and
social skills, and personality changes.
 It is the fourth largest cause of death in
Australia.
 Postmortems of people who have had
Alzheimer’s shows that the brain appears to
have rusted, deposits of plaque bound together
like blobs and there are visible tangles of brain
fibre.
 It
is estimated that the disease affects:
- 1 in 25 over 50
- 1 in 8 over 65
- 1 in 4 over 80
 It also affects some people in their 50’s.
 An accurate diagnosis of this disease can only be
made after death when an autopsy can be done.
 Diagnosis can be difficult as there is no one
symptom that is reliable.
 Memory
loss will include:
Events
- Words or names
- Written and verbal directions
- Stories on TV, in movies or books
- Stored knowledge
- Everyday skills
 Severe personality changes are also observed in
patients with Alzheimer’s.
-
 In
the latter stages of Alzheimer’s patients will
struggle to undertake even the simplest everyday
tasks.
 They may become unable to remember their own
family members and eventually forget their own
identity.
 The thing that distinguishes Alzheimer’s from other
diseases is that it includes both loss of past
memories (retrograde) and difficulties retaining
new information (anterograde).
 Autopsies
reveal high levels of the protein amyloid
in the brains of people with Alzheimer’s.
 This is not usually found in the brain and is toxic,
poisoning the brain cells.
 It causes abnormal structures to form called
plaques and tangles.
 Plaques are dense deposits of protein outside the
neuron and tangles are twisted fibres that build up
around the neuron.
 The area of the brain most affected is the
hippocampus.
 There
is currently no cure for Alzheimer’s disease,
however some medications can slow the
progression.
 Most
people believe that memory decline is a
natural part of ageing.
 Research
shows however, that although there is
some natural decline in memory with age, memory
is not an inevitable consequence of ageing.
 If
a decline in memory is experienced through
ageing, effects are more likely to be experienced in
working memory and the declarative memory
systems (episodic and semantic memories) than in
procedural memories.
 The
impact of age on STM seems to depend on the
nature of the task.
 If the task is simple it should not be affected by
age.
 If the task is more complex, age related factors
may impact on effective STM functioning.
 One study shows that when storage and
manipulation of information is required younger
participants scored higher (3.2 words out of a list)
than their older counterparts (1.7 words out of a
list)
 Neuroimaging studies have shown that beyond 60
years of age, there is a decrease in the activation
of areas of the frontal lobes of the brain believed
to be involved in STM.
 Research
findings indicate that some LTM
stores are more likely to be affected by age
than others.
 Episodic
memory is the most likely to decline
with age and this decline can start as early
as 30 or as late as 50.
 Although
many semantic and procedural
memories are not easily lost, older people
take longer to learn new information and
skills.
 It
seems that older people do not encode new
information with as much detail or as precisely as
young people.
 The
speed and fluency of retrieval of information
from semantic memory is particularly prone to
decline.
 One
explanation for this is lack of motivation.
 There
is however less age-related decline for
memory tasks in which a person is motivated to
remember something. Eg. Taking a cake out of the
oven.
A
second explanation is that as people get older
they tend to lose confidence in their memory.
A
third explanation is that the inability of some
older people to access information from LTM may
be more to do with the kind of measure of
retention used that with their age.
 The
most common reason is a process called
cognitive slowing. This refers to the slowing of
Central Nervous System functioning and the
inability to effectively process information the way
a person may once have.
 This
occurs because the frontal lobe shrinks as age
progresses and therefore cognitive function is
influenced by this process.