Memory
Short-Term Memory & Working Memory
THE MULTI-STORE MODEL OF MEMORY

Sensory store
Holds sensory information for a very brief time
 Information not attended to is lost


Short-term memory (STM)
Holds information for limited time
 7-9 items capacity
 Information not rehearsed is displaced
 Once rehearsed information is transfered to LTM


Long-term memory (LTM)
Permenant memory store
 Unlimited

ATKINSON & SHIFFIN MODEL
SENSORY MEMORY

Iconic store


Visual information is stored
Echoic store

Auditory information is stored
SHORT-TERM STORE


Example: To remember a telephone number
Limited capacity and fragile storage

Any distraction causes forgetting
The recency effect:



Last few items in a list are better remembered that the first or middle
words.
The primacy effect:

First few words remembered better than the middle words.
SHORT-TERM STORE-Duration

Peterson and Peterson (1959)

Task of remembering three letters while counting backwards by threes.

The ability to remember the three letters declined to 50% after 6
seconds.

This indicates that information is lost from short-term memory rapidly.

This may be because counting backwards results in interference or
diverts attention away from STM.
SHORT-TERM STORE: Rehearsal

Rehearsal maintains information in short-term memory.

Words that are shorter and can be rehearsed rapidly should
remain in STM.

Words that take longer to reheasre will decay from STM.

Some evidence supports this while others do not.

Studies which do not support it cast doubt on the fact that short-term
memory depends on rehearsal.
SHORT-TERM STORE: Forgetting

Forgetting from STM:

Decay

Proactive Interference (disruption of current learning by previous learnt
material).

Example: Trying to study cognitive psychology after studying for
neuropsychology.

Neuropsychology inteferes with cognitive psychology learning.
WORKING MEMORY
Baddeley and Hitch (1974) and Baddeley (1986)

Central Executive

Resembles attention

Controlling unit


Phonological Loop


Stores speech-based information
Visuo-spatial sketchpad


Limited capacity
Stores visual-based information
Episodic buffer

Integrates information from the Visuo-spatial sketchpad and Phonological
loop. Controlled by the Central Executive
WORKING MEMORY
WORKING MEMORY
WORKING MEMORY

Assumptions

If two tasks use the same componet, they cannot be performed
successfully together.

If two tasks use different components, it should be possible to
perform them well together.
WORKING MEMORY
PHONOLOGICAL LOOP

Phonological Similarity Effect

Recall of words is better when words sound different than when they
sound the same.

Example: Recall is better for words such as UP and ODD, than HE
and KNEE

Speech based reherasal within the phonological loop
WORKING MEMORY
PHONOLOGICAL LOOP

Word Length Effect

Better recall of shorter words than longer words.

Takes longer time to rehearse the longer words which causes greater
levels of decay.
WORKING MEMORY
PHONOLOGICAL LOOP

A passive phonological store directly concerned with speech
production


An articulatory process linked to speech production that gives access
to the phonological loop


Auditory presentation of words gain direct access to the phonological store
Words presented visually need to be articulated then gain access to the
phonological store – access is therefore indirect
Word length effect therefore is dependent on articulatory rehearsal
PHONOLOGICAL LOOP
VISUO-SPATIAL SKETCHPAD

Temporary storage and manipulation of spatial and visual
information.

Two components:

The visual cache


Stores information about visual form and colour.
The inner scribe

Deals wıth spatial and movement information.

Rehearses information in the visual cache.

Tranfers information from the visual cache to the central executive.

Involved in the planning and execution of body and limb movements.
CENTRAL EXECUTIVE

Most important component of working memory.

Damage to the frontal lobes can cause impairements to the
central executive.

Functions:

Switching attention between tasks.

Planning subgoals to achieve goals.

Selective attention and inhibition.

Updating and checking the contents of working memory.

Coding representations in working memory for time and place of
appearance.
CENTRAL EXECUTIVE

Single or multiple central executive functions?

Evidence favours the latter (i.e., multiple)

Three central executive functions:


Shifting attention

Updating information

Response inhibition
All share common processes (e.g., attention) but also function
independently.
EPISODIC BUFFER

Stores and intergrates information from both the phonological
loop and visuo-spatial sketchpad.
MEMORY PROCESSES

Encoding

Storage

Retrieval
TESTS OF MEMORY



Free recall

Hardest type of recall

Least environmental support
Cued recall

Second hardest type of recall

Provides some environmental support
Recognition

Easiest type of recall

Memory best under recognition

Provides environmental support
TEST OF MEMORY


Explicit Memory

Conscious and deliberate retrieval of past events

Exam
Implicit Memory

Memory not involving consious recollection

Word stem completion

Complete the word ‘Ten___’
LEVELS OF PROCESSING
Craik and Lockhart (1972)

Attentional processes at learning determine what information is
stored in long-term memory.

Various levels of processing

Shallow processing:


Physical analysis of stimuli.
Deep or semantic processing:

Analysis of meaning.

Deep or semantic processing produce more elaboration, longer lasting and
stronger memory traces than shallow processing.
LEVELS OF PROCESSING
Craik and Lockhart (1972)

Two types of rehearsal:

Maintenance rehearsal


Repeating information to remember it.
Elaborative rehearsal

Involves semantic-meaning processing.

Information which is sematically processed will be trasnfered to long term
memory.
ELABORATION
Craik and Tulving (1975)

Elaboration of processing is important

Aids LTM

The kind and amount of elaboration is critical for recall

Precise semantic encodings are better
DISTINCTIVENESS
Eysenck (1979)

Distinctive or unique memory traces are recalled more than non
distinctive memory traces.
THEORIES OF FORGETTING

Ebbinghause studied forgetting with himself being the only
participant.

He learned and recalled a list of nonsense syllables which had
no meaning over several trials.

Forgetting was very rapaid over the first hour after learning
which slowed down thereafter.
REPRESSION

Freud argued that anxiety provoking material is often unable to
gain access to conscious awareness, known as repression.

Adaptive function to maintain psychological well-being.
INTERFERENCE THEORY

Dominant approach

Ability to remember currently learned information can be
disrupted with previously learnt material or what we learn in the
future.

Proactive Interference


Previous learning interferes.
Retroactive Interference

Later learning disrupts earlier learning.
CUE-DEPENDENT FORGETTING
Tulving (1974)

Trace-Dependent Forgetting


Information is no longer stored in memory
Cue-Dependent Forgetting

Information is stored in memory but cannot be accessed

Cue-dependent forgetting associated with external cues (categories)
and internal cues (mood)

If the mood of retrieval is different from learning information will be
blocked

The mood effect is stronger for positive than negative moods and for
personal events
CONSOLIDATION

Is a process lasting for several hours or even days which fixes
information in LTM.

‘New memories are clear but fragile and old ones are faded but
robust’ (Wixted, 2004, p.265).

Consolidation process for one memory can be distrupted by
other memories, so better consolidation will take place during
sleep than awake as fewer memories are being formed.
CONSOLIDATION

Sleep will aid the consolidation period early in the retention
interval, as, thats when memories are vulnerable to disruption.

Those who slept after learning remembered 81% than those who
slept later 66%.