Memory Short-Term Memory & Working Memory. THE MULTI-STORE MODEL OF MEMORY Sensory store Holds...

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Memory

Short-Term Memory & Working Memory

THE MULTI-STORE MODEL OF MEMORYSensory 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: Trying 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 MEMORYBaddeley and Hitch (1974) and Baddeley (1986)

Central Executive Resembles attention Controlling unit Limited capacity

Phonological Loop Stores speech-based information

Visuo-spatial sketchpad 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 MEMORYPHONOLOGICAL 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 MEMORYPHONOLOGICAL 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 MEMORYPHONOLOGICAL LOOP

a) A passive phonological store directly concerned with speech production

Auditory presentation of words gain direct access to the phonological store

b) An articulatory process linked to speech production that gives access to the phonological loop

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 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 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)-two reasons for forgetting 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 coz 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%

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