REMEMBERING & REMEMBERING & FORGETTINGFORGETTING

Models of Memory– Multi-store Model– Working Memory Model– Levels of Processing

Types of Memory– Semantic– Procedural– Episodic

(incl. Autobiographical)

PYSB2 COGNITIVE PSYCHOLOGY

Explanations of Forgetting

• Trace Decay• Displacement• Interference• Retrieval Failure• Lack of Consolidation• Motivated Forgetting (incl. Repression )

The study of Cognitive Processes is also called the

approachINFORMATION PROCESSING

EncodingEncodingInformation is

INPUT by selecting and

changing it into a format that can be stored.

Retrieval Retrieval Information is RECALLED in

the same format that it is

stored. (the OUTPUT)

Remembering involves three basic processes called THE THREE STAGES OF MEMORY

StorageStorage Information

is STORED in its encoded

format.

However there could be several different types of store.

Our own experience (Introspection) would suggest that there are at least two very different types of memory

store.

Short Term Memory (S.T.M.)Short Term Memory (S.T.M.)Where information is held for a short time.

Also called Primary Memory or Working Memory. It enables us to hold a conversation and to pay attention to

our immediate surroundings. Without it we could not function.

Long Term Memory (L.T.M.)Long Term Memory (L.T.M.)Where information is held for a longer time, perhaps permanently. Also called Secondary

Memory. It enables us to remember events from the past, and all that we have learnt. Without it we would not exist as individuals.

Next we need to establish how information is ENCODED, STORED and RETRIEVED in each store.

http://aqa.psychblog.co.uk/wp-content/uploads/multistoremodel.swf

(Atkinson & Shiffrin 1968)

The Multi-Store Model of Memory

S.M.S.M.Sensory Memory

L.T.M.L.T.M. Long Term

Memory

S.T.M.S.T.M. Short Term

Memory

For an animated version visit -

SENSORY INPUT

ATTENTIONRETRIEVAL

ENCODINGENCODING

INFO LOSS

“forgetting” INFO LOSS

forgetting

REHEARSAL LOOP

Sensory Memory

By Sensory

modality.ENCODING

• S.T.M. • L.T.M

DURATION

CAPACITY

Acoustically(sometimes visual)

Semantically

Evidence? SPERLING BADDELEY BADDELEY

½ - 2 secs 18 – 30 sec Life time?

SPERLING PETERSON & PETERSON

Very limited

7 + or - 2 Infinite?

SPERLING MILLER

Evidence?

Evidence?

WORKING MEMORY MODEL(Baddeley & Hitch 1974)

The CENTRAL EXECUTIVE controls working memory by focusing attention on one or more of sub-systems and determines flow into LTM.

The VISUO-SPATIAL SKETCHPAD encodes and stores visually, limited in capacity and duration.

The PHONOLOGICAL

LOOP consists of ?

and the PHONOLOGICAL STORE which also has a limited capacity.

the ARTICULATORY PROCESS encodes acoustically and uses REHEARSAL to process information.

You can illustrate working memory works by asking how many windows in your house?

Components of the ….

Craik and Lockhart (1972) suggested that information can be processed at different levels.

Visual Visual by appearance eg: starts with capital letter

the key to remembering information in LTM by processing at a deeper level – analyse it, associate

it with things already in LTM, make it more meaningful.

LEVELS OF PROCESSING THEORY

Phonetic Phonetic by sound, eg: rhyme’s with ….?

Semantic Semantic by meaning, eg: associated with?

The deeper we process the information the better we remember it in LTM.

SHALLOW PROCESSINGNeeds less thinking

DEEP PROCESSINGMore thinking involved

ELABORATION is

Evaluating Models of Memory

Multi Store

+ Has lots of empirical evidence to support it ; Miller (1954) , Peterson & Peterson (1959), Baddeley (1966)

- Evidence lacks ecological validity (limited materials).

+ Simple to understand. - It oversimplifies memory.

Levels ofprocessing

WorkingMemory

+ Evidence from Craik & Tulving (1975) shows that deeper processing gives better recall from LTM.

- What is deep? this could vary with individuals

- Does not explain role of emotion and motivation

+ Evidence from Baddeley & Hitch (1974) shows that we can process more than one task using STM.

+ Helps to explain multi-tasking & learning difficulties

- Does not explain how central executive works

Types of Long Term MemoryLong Term MemoryOur “how to” memory, eg: riding a bicycle we

may not be able to explain it in words or even know that we have this memory. Little research has been done on this.

ProceduralProcedural

The case study of CLIVE WEARING illustrates how these can function independently and how even if only one of these are

damaged the effects can be devastating.

Our “know it” memory, eg: capital of France because it is processed by meaning it is organised in the way it was originally learnt. Most memory research has looked at this.

SemanticSemantic

Our “episodes of life” or autobiographical memory, eg: last holiday, sixteenth birthday.

Includes Flashbulb Memories which are vivid, emotive memories – ( eg 9/11 ).

EpisodicEpisodic

Explaining

Forgetting

• Not really wanting to recall

In which of the three stages of memory could forgetting occur?

ENCODING STORAGE RETRIEVAL

• Time

• Confusing information

• Too much stuff to remember

• Alcohol etc.

Each of these is explained by a different theory your challenge is too work out which applies to which stage, store and type of

Memory.

From introspection suggest some factors that could lead to forgetting ?

• Brain Damage

The simple idea that memories are lost over time is called

TRACE DECAY

First proposed by Hans Ebbinghaus in 1885 based on testing his own memory for non-sense syllables (such as BEJ, ZUX) which had no

associations.

However he also found that it did not take so long to remember these items the second time around. He called this his “SAVINGS”

RE

CA

LL

%

TIME = DAYS

Ebbinghaus found that his memory decayed over time, called the

“FORGETTING CURVE”.

This is NOT an adequate explanation for forgetting in LTM because -• Something must have remained in LTM as it could be re-learnt faster• Older meaningful memories of important events can often be

remembered better than newer but less relevant ones.

Trace Decay in STM?

Instructions:- Read the consonants that appear below then count backwards in three’s from the number given. Write down the letters you recall when asked.

Student Exercise

MemEx1

L Z M , P V Q, X F D

B F Y , G Z J, P D L

K M R , H G Y, J T Z

M Q L , T L Y, F R N

763 STOP! WRITE NOW!

435

917

329

STOP! WRITE NOW!

STOP! WRITE NOW!

STOP! WRITE NOW!

Interference task practice – count back

in three’s from 333.

This shows that the longer the interval before recall the more items that are lost from memory. This is what we would expect because Peterson & Peterson showed that the duration of S.T.M. is between 18 – 30 secs.

Trace Decay OR Trace Decay OR Interference?Interference?

But Peterson & Peterson also found that as the trails when on participants confused earlier trigrams with later

ones, raising the question was this forgetting due to ..

Jenkins & Dallenbach(1924) showed that nonsense syllables learnt in the evening would be remembered better than those learnt in the morning, even though the same amount of time had past.

They concluded that the events of the day had “interfered” with the memory for the nonsense syllables more than when people are sleeping.LTM – INTERFERENCE provides a better explanation than trace decay.

STM – TRACE DECAY & INTERFERENCE can BOTH be used.The memory store that TRACE DECAY applies to best is SENSORY MEMORY.

SPERLING’S (1960) experiment demonstrates this. It also makes sense in terms of our experience of sparklers, traffic lights at night & sound echo.Interference is forgetting due to confusion with previous or later material. It can effect STM or LTM.

PROACTIVEPROACTIVE Where information

learnt earlier interferes with that

learnt later.

INTERFERENCEINTERFERENCERETROACTIVERETROACTIVE

Where information learnt later

interferes with that learnt first.

For example you are learning Spanish this

year, last year you leant French.

Interference theory :-

•explains forgetting in STM & LTM when material is similar

•works better for episodic memory than semantic

•research lacks ecological validity – when do we use non-sense syllables or trigrams in everyday life?

Qu. What is it if John calls his current girlfriend by the name of his ex?

Is the simple idea that new memories will replace old ones

DISPLACEMENT

This theory assumes that a memory store has a limited capacity, so which types of memory will it apply to?

Miller (1956) found that when STM was full up (5 – 9 items) new material would push out the old.

This is NOT an adequate explanation for forgetting in LTM because -• As far as we can tell LTM has an unlimited capacity.• We can recover memories that we thought were forgotten.

NEW INFORMATION INPUT

OTHER INFORMATION

IS LOSTS.T.M.

7+-2 items

Also Sperling (1960) found that SENSORY MEMORY also has a very limited capacity so this theory would also explain forgetting here but-

Which theory best explains the Serial Position Effect?

Primacy Effect

Recency Effect

Both Pro-active & Retro-active Interference

Retro-active Interference

only

Pro-active Interference only

Does not explain why earliest material is remembered better (Primacy Effect) than the material in the middle which came latter.

Explains why material is lost from middle and why less is lost from the end (Recency Effect) but it does not explain the primacy effect.

Offers best explanation, material in middle of curve is subject to both Pro-active & Retro-active interference, but the material at start and end of the list only one of these.

TRACE DECAY?

DISPLACEMENT?

Serial Position Curve

INTERFERENCE?

Can you think of examples from LTM when this may not be the case?

A failure to encode information in LTM could also be caused by some external event which wipes the memory

store in STM, here forgetting is due to the –

Lack of ConsolidationLack of ConsolidationS.T.M. L.T.M.Due to trauma, concussion,

alcohol, drugs, E.C.T. etc.

Yarnell & Lynch (1970) showed that concussed American footballers could recall what happened if asked immediately (STM) but could not recall anything when asked 20 minutes later (LTM).

Electro-convulsive therapy (ECT) seems to wipe memory of events up to one hour before, suggesting that consolidation takes some time.

This is a good way of explaining some forms of amnesia, but the biological mechanisms of memory are not fully understood so it is difficult to describe exactly how it works.

If information has been encoded and stored successfully in LTM but still cannot be remembered then this could be due to

– Retrieval Retrieval FailureFailure“Tip of the Tongue” is a common experience when we simply need

the right clue (or Cue) to help us recall something.

Also called Cue Dependant Forgetting

The cue usually relates to the conditions of encoding, in semantic memory it often organisational – eg: categories.

State Dependant State Dependant forgettingforgetting

Context Dependant Context Dependant forgettingforgetting

Is when your internal state, mood or condition at the time of encoding information provides a cue to remembering it.

Is when the environmental factors at the time of encoding information provides a cue to remembering it.

Godden & Baddeley (1975) showed that divers who learnt a list of words underwater recalled it better underwater than on land and vice versa.

WORDS WORDS WORKS

MOTIVATED FORGETTING – is the idea that we forget some things (from LTM) because it is not in our best interests to recall them; this could be due to ..RepressionRepression

Freud (1901) suggested that this Ego Defence Mechanism protected the conscious part of the mind (Ego) from the primitive, socially unacceptable drives in the unconscious mind (Id).

Glucksberg & Lloyd (1967) showed that words associated with other words that were accompanied by an mild electric shock were not recalled as well as controls.

Levinger & Clark (1961) showed that words associated with emotionally negative words (eg: cancer, anger) were not recalled as well as those associated with neutral words.

Both are lab experiments and have being criticised on methodological and ethical grounds, they are also subject to alternative explanations.

Williams (1994) interviewed 129 women 17 years after they had been sexually abused as children, 38 % did not mention the abuse. He concluded that they had repressed the memories. Can you provide an alternative explanation.