Memory
Memory - The storage and retrieval of information acquired through learning.
Information Processing Model
Encoding – the process of converting information into a useable form or ‘code’, so that it can enter and be stored in
memory.
Two types of encoding: automatic and effortful.
Automatic – information that is encoded without deliberate mental effort. Usually information about a person’s
location in space and time.
Effortful – deliberate, mental effort is required to retain specific information.
Storage – the retention of information over time.
Retrieval – the process of locating and recovering the stored information from memory.
 Youtube – Autobiographical Memory Marilu Henner
 www.improvememory.org/games
Multi-store model of memory – Atkinson and Shiffrin
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3 distinguishable components called the sensory register, short-term store and long-term store.
Information is held and processed in each and information passes through each.
Each system encodes, stores and processes information in different ways.
The systems operate simultaneously and interact.
Sensory memory
Entry point of memory where new incoming sensory information is stored for a very brief period of time.
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Sensory memory is made up of different sensory registers. One for each of the senses.
Information is stored as an exact copy of the original.
Duration: 0.2 seconds up to 4 seconds.
Capacity: unlimited
When information is attended to it is transferred to STM and we become consciously aware of it and encode
it for permanent storage.
If not attended to the information is lost very quickly and cannot be stored permanently.
Two sensory registers: iconic and echoic.
Iconic Memory
Visual sensory memory that stores visual images in their original sensory form for between 0.2 and 0.4 seconds.
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Capacity: unlimited
Duration: 0.2-0.4 seconds
Sperling – iconic memory test, only 4 or 5 letters could be recalled before letters faded from the sensory register.
Could recall words from any line when asked (capacity). Tested different lengths of time between reporting to find
out duration of iconic memory.
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 Learning activity 6.5 (questions 1-5)
Echoic Memory
Auditory sensory memory that stores sounds in their original sensory form for up to 3 or 4 seconds.
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Capacity: unlimited
Duration: 3-4 seconds
All sounds
3-4 seconds allows for attention to switch to sounds and transfer information to STM
Individual sounds are processed. Parts of speech are heard separately and must be stored long enough for
the whole word to be put together to create meaning.
Short Term Memory (STM)
A memory system with limited storage capacity in which information is stored for a limited time (relatively short
period of time) unless renewed in some way.
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Capacity: 7 ± 2 pieces of information
Duration: 12-30 seconds
STM test:
http://faculty.washington.edu/chudler/stm0.html
Methods to increase STM
Chunking
The grouping of separate bits of information into larger ‘chunks’.
Rehearsal
Information can be kept longer in STM if rehearsal is used.
Rehearsal is the process of consciously manipulating information to keep it in STM, to transfer it to LTM or aid
storage and retrieval.
Two types of rehearsal: maintenance and elaborative
Maintenance Rehearsal: rote learning, repetitive and keeps information in STM, does not assist encoding for storage
in LTM.
Information kept in STM through maintenance rehearsal restricts the amount of new information that can enter
STM.
Elaborative Rehearsal: linking new information in a meaningful way with other new information or information
already stored in LTM.
Elaborative rehearsal is a more active and effortful process than maintenance rehearsal – important for encoding.
Self-referencing effect- relating new information to personal experiences to create meaning and therefore
remember it.
 Learning activity 6.10, page 312
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Craik and Lockhart’s Levels of Processing Framework
The level or ‘depth’ at which we process information during learning, determines how well it is stored in LTM.
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More meaning = better storage in LTM
Continuum of levels ranging from shallow to deep
Information retained briefly if processed on a shallow level
Information retained longer if processed on a deep level
Semantic = meaning
 Learning Activity 6.12, page 315
Working Model of Memory – Baddeley and Hitch
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An alternate explanation of STM
3 components: phonological loop, visuo-spatial sketchpad and central executive.
Components are separate and act independently, but also interact
Phonological loop = verbal (auditory) information
Visuo-spatial sketchpad = visual and spatial information
Central executive = manages the activities of the other three components (sub-systems)
Phonological Loop
Temporarily stores a limited amount of verbal, speech-like information, such as sounds of words for a brief period of
time (2 seconds).
- Sub-vocal maintenance rehearsal ‘loops’ the information to keep it in working memory.
Visuo-spatial sketchpad
Temporarily stores a limited amount of visual and spatial information for a brief time.
- Visual information is anything we can see and visualise (images)
- Spatial information is the location of objects in space
Central executive
Controls attention and integrates information from the phonological loop and visuo-spatial sketchpad, as well as
information retrieved from LTM.
- Controls the flow of information between working memory and LTM
- Central executive manipulates information, directs our attention: the ‘working’ part of working memory
- Can only perform one task at a time
Example: taking notes – executive directs attention to the board. Visuo-spatial sketchpad identifies the images to
transfer to the page, phonological loop repeats words sub-vocally during transfer from board to page. Visuo-spatial
sketchpad also takes note of location of each word or the spelling (order of letters). Executive retrieves information
from LTM, such as how to spell words without re-checking the board.
Fourth component added to model: Episodic buffer
Episodic buffer
A sub-system of working memory that enables the different components of working memory to interact with LTM.
- Holds 4 chunks of information (in any form)
- Combines other sub-systems and information from LTM to form episodes or ‘movie scenes’ of life
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Long Term Memory
Relatively permanent memory system that holds vast amounts of information for a long time.
Two types of LTM: Procedural and Declarative
Procedural
Memory of actions and skills that have been learned previously.
- The ‘how to’ or ‘knowing how’ part of memory
Declarative
Memory of specific facts or events that can be explicitly stated or ‘declared’.
- The ‘knowing that’ part of memory
- Two types: semantic and episodic
Episodic:
- memory of specific events or personal experiences
- AKA autobiographical memory (Marilu Henner)
Semantic:
- Memory of information we have about the world
- Facts that we know, but generally can’t recall exactly when we learnt them
 Activity 6.18, page 326
Organisation in LTM
 Activity 6.20, page 328
Semantic Network Theory
Information in LTM is organised systematically in the form of overlapping networks of concepts that are
interconnected and interrelated by meaningful links.
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Concepts are called ‘nodes’
Nodes are linked together
Activating one node, activates other nodes linked to it
The shorter the link between nodes the stronger the association between them and the less time it takes to
retrieve information
More nodes activated = quicker retrieval
Serial Position Effect
Free recall is better for items at the beginning and end of a list, than the middle.
Two effects: Primacy effect and recency effect
Primacy effect: superior recall of items at the beginning of a list.
Recency effect: superior recall of items at the end of a list.
 Activity 6.25, page 334
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Neural basis for memory
The role of the neuron in memory formation – Kandel
Kandel experimented on Aplysia (sea slugs). His research suggests that, during learning, neurons increase production
of neurotransmitters ejected into the synapse, resulting in an increase in synaptic transmission and the formation of
a chemical trace of the information.
Three changes to the neurons of Aplysia:
1. Function – more neurotransmitters are released
2. Axons and dendrites create more branches to strengthen connections between neurons
3. Synaptic growth – more synaptic connections are formed that also strengthen connections between neurons
STM storage – increase in release of neurotransmitter, but no structural changes.
LTM storage - all three changes occur
Hippocampus
Assists memory formation, sorting and storage and the transfer of information from STM to LTM. Damage can lead
to permanent short-term and long-term memory dysfunction. People with hippocampal damage find it difficult to
learn new factual information, however, their ability to learn new skills or procedures appears unaffected.
Temporal lobe
Assists in memory of language specifically for naming familiar objects, places and faces and for constructing fluent,
articulate and coherent speech. Also involved in the memory of facts, personally significant events and familiar
routines.
The left temporal lobe stores information such as names of familiar people, animals and tools as well as factual
information and personal event that can be expressed in words.
The right temporal lobe stores information for recognising familiar faces, music and pictures.
Consolidation theory
The theory that it takes approximately 30 minutes for information to be transferred from STM to LTM, during which
time brain cells change as a chemical memory trace of the information is laid down. Interruptions to the
consolidation process can result in information loss or damage.
Amnesia; neurodegenerative diseases.
Amnesia
Involves permanent or temporary, partial or complete memory loss.
Retrograde Amnesia is memory loss for events prior to the amnesia-causing event.
Backward acting memory loss. Retrograde amnesia is usually temporary. The period of time immediately before the
accident or trauma is never recovered.
Anterograde Amnesia is memory loss following the amnesia causing event.
Forward acting memory loss. New memories cannot be formed.
Korsakoff’s Syndrome is a neurodegenerative disease involving damage to brain structures and occurs mainly in
chronic or long-term alcoholics. The disease is linked to a deficiency of vitamin B in the diet. People with this
syndrome have difficulty forming new memories.
Neurodegenerative diseases
A disease characterised by a progressive decline in the structure, activity and function of brain tissue.
Neurons are damaged or die and lose their function. This tends to happen as we age.
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Dementia
Dementia is a term used to describe a variety of symptoms of a large group of illnesses that cause a progressive
decline in a person’s mental functioning.
Most common symptoms: memory loss, decline in intellectual ability, poor judgment, poor social skills and abnormal
emotional reactions.
Memory loss is typically the first symptom.
Alzheimer’s disease is the most common form of dementia.
Alzheimer’s Disease
An irreversible, progressive and fatal neurodegenerative disease that attacks the brain and kills brain cells, causing
severe cognitive and behavioural decline.
Symptoms: memory loss, forgetfulness, confusion, poor judgment, disorientation, impaired attention. As it
progresses, mood and personality can change and loss of other functions (ability to talk, walk, control bladder, etc)
can occur.
Earliest damage occurs in the hippocampus. This is slowly followed by a loss of neurons and synapses in the cerebral
cortex, particularly in the temporal lobe, parietal lobe and frontal lobe.
There is no single known cause of Alzheimer’s disease. There are unusual webs and tangles in brain cells leading to
and from the hippocampus. This causes the neurons to die and the brain shrinks.
Amyloid placques form in the brain. Amyloid is a protein. The placques collect on the outside of neurons and attach
to them. The amyloid reacts with the copper and iron which are naturally occurring in the brain and ‘rust’ the
neurons. This destroys the synapses and neural messages can no longer be sent.
In Alzheimer’s disease the brain also has neurofibrillary tangles, an abnormal build-up of proteins within neurons.
The placques and tangles disrupt the normal organisation and communication between brain cells, causing them to
die.
Alzheimer’s brains also have lower levels of the neurotransmitter acetylcholine, which plays a role in the formation
of memory.
First decline in declarative memory, followed by procedural memory, as the disease progresses.
Memory decline over the lifespan
Memory function does not automatically decline with age, but information is processed more slowly. This is due to
the slowing down of the nervous system.
Memory performance for older people can be influenced by the retention measure chosen, the memory type tested,
the meaningfulness and complexity of learnt information, the person’s attitude to their memory ability, t he effort
they put into memorising information and how they actively try to strengthen their memory.
Older people will be able to remember more information if asked to recognise it, rather than recall it.
Episodic memory is affected more by normal ageing than other memory types.
Revision
 Chapter 6 Test – multiple choice questions (page 356)
 Student Activity Manual – Activity 4.1 (Part B) page 105
 Student Activity Manual – Activity 4.2 (Part A, B, C) page 106-108
 Student Activity Manual – Activity 4.3 (Part A, B, C) page 108-111
 Student Activity Manual – Activity 4.4 (Part B) page 113
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Forgetting
Forgetting: an inability to retrieve previously stored information from long-term memory.
Ebbinghaus’ Forgetting Curve
- Ebbinghaus’ forgetting curve shows the typical amount and rate of forgetting for newly learnt information
over time.
- The forgetting curve shows that forgetting is most rapid immediately after learning, but then slows down
until the amount of forgotten information plateaus.
- Hermann Ebbinghaus favoured the use of nonsense syllables in his memory experiments because these are
not linked with prior knowledge or experience.
- Althoug the shape of the forgetting curve remains the same, forgetting is much slower for meaningful
information.
Measures of retention
Recall: the least sensitive measure of retention and involves reproducing information using few to no cues. There are
three types of recall: free recall (no cues), cued recall (some cues) and serial recall (ordered recall, no cues).
Recognition: is a more sensitive measure of retention than recall. It involves selecting the correct alternative from a
list of possible alternatives.
Relearning: is the most sensitive measure of retention. It involves learning information that has been previously
learnt, as a means of assessing whether any information was retained from original learning. This is calculated using
the savings score.
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Student Activity Manual – Activity 5.2
Student Activity Manual – Activity 5.4
Student Activity Manual – Activity 5.5
Learning activity 7.3 in textbook
Extended Response
Using the Multi-store Model of Memory, describe how Alzheimer’s disease effects memory. Include the relevant
brain structures in your response. (15 marks)
Theories of forgetting
1. Retrieval failure
Forgetting occurs because we cannot access the correct retrieval cues to access the required memory.
2. Interference theory
Forgetting occurs when other information blocks our retrieval of specific information. There are two types of
interference: proactive interference is when old memories block the retrieval of recently learnt information;
retroactive interference is where new information blocks the retrieval of old memories.
3. Motivated forgetting
Forgetting occurs because we block painful or threatening memories from our conscious awareness. This may be
due to repression (forgetting without conscious awareness) or suppression (conscious forgetting).
4. Decay theory
Forgetting occurs because memory traces deteriorate over time due to lack of use.
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Memory cues
Context-dependent cues: aid retrieval by recalling the information in the same place or setting as that in which it
was learnt.
State-dependent cues: aid retrieval by recalling information while in the same physical or psychological condition as
that in which it was learnt.
Mnemonic devices
Mnemonics: techniques for enhancing or improving memory.
1. Narrative chaining: creating a story that sequentially links the words to be remembered.
2. Method of loci: using a well-known series of locations to visually associate with words to be remembered.
3. Acronyms: constructing a word using the first letter of each term to be recalled.
4. Acrostics: creating a sentence using the first letter of each word to be recalled.
5. Peg-word method: using a specific rhyme to associate with words to be remembered.
Learning activity 8.7 page 408
Context and State dependent cues
Context-dependent cues: are environmental cues in the specific situation (context) where a memory was formed,
which act as retrieval cues to help access the memories formed in that context. These cues may include the sights,
sounds and smells within that specific situation.
State-dependent cues: are associated with an individual’s internal physiological and/or psychological state at the
time the memory was formed, which act as retrieval cues to help access those memories. For example, if
information is learned when you are happy, sad, intoxicated, etc.
Reconstructing memories
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Memory reconstruction involves remembering past events and features of these events and putting them
together during memory recall.
Research conducted by Sir Frederic Bartlett found that individuals fit new memories into their existing
knowledge and personal experiences (their schema), leading to inaccurate reconstruction of memory.
Eye-witness testimony can be influenced by leading questions and language use.
Research conducted by Loftus has found that when asked leading questions such as “Did you see children
get off a school bus?” participants were more likely to report seeing a school bus a week later compared to
those who were not asked the leading question.
There is also evidence to suggest that emotive language such as ‘car smash’ as opposed to ‘car crash’ will
result in an increase of reported damage at the scene of a crime.
Leading questions, the wording of questions can manipulate memory.
Studies conducted by Loftus and Palmer (1974) – Learning Activity 8.3 (page 398)
Extended Response: What are cues? Compare and contrast the different cues that aid memory formation and
retrieval. Also include a description of how they are involved in forgetting. 12 marks
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