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PYSB2. COGNITIVE PSYCHOLOGY. REMEMBERING & FORGETTING. Explanations of Forgetting Trace Decay Displacement Interference Retrieval Failure Lack of Consolidation Motivated Forgetting (incl. Repression ). Models of Memory Multi-store Model Working Memory Model
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PYSB2 COGNITIVE PSYCHOLOGY REMEMBERING & FORGETTING Explanations of Forgetting • Trace Decay • Displacement • Interference • Retrieval Failure • Lack of Consolidation • Motivated Forgetting (incl. Repression ) Models of Memory Multi-store Model Working Memory Model Levels of Processing Types of Memory Semantic Procedural Episodic (incl. Autobiographical)
Remembering involves three basic processes called THE THREE STAGES OF MEMORY The study of Cognitive Processes is also called the approach EncodingInformation is INPUT by selecting and changing it into a format that can be stored. StorageInformation is STORED in its encoded format. Retrieval Information is RECALLED in the same format that it is stored. (the OUTPUT) INFORMATION PROCESSING However there could be several different types of store.
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. Our own experience (Introspection) would suggest that there are at least two very different types of memory store. 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.
The Multi-Store Model of Memory (Atkinson & Shiffrin 1968) ATTENTION S.M.Sensory Memory S.T.M.Short Term Memory RETRIEVAL L.T.M.Long Term Memory SENSORY INPUT ENCODING ENCODING INFO LOSS “forgetting” INFO LOSS forgetting REHEARSAL LOOP For an animated version visit - http://aqa.psychblog.co.uk/wp-content/uploads/multistoremodel.swf
Sensory Memory • S.T.M. • L.T.M By Sensory modality. Acoustically(sometimes visual) Semantically ENCODING SPERLING BADDELEY BADDELEY Evidence? ½ - 2 secs 18 – 30 sec Life time? DURATION Evidence? SPERLING PETERSON & PETERSON Very limited 7 + or - 2 Infinite? CAPACITY Evidence? SPERLING MILLER
WORKING MEMORY MODEL Components of the …. (Baddeley & Hitch 1974) the ARTICULATORY PROCESS encodes acoustically and uses REHEARSAL to process information. The CENTRAL EXECUTIVE controls working memory by focusing attention on one or more of sub-systems and determines flow into LTM. The PHONOLOGICAL LOOP consists of ? The VISUO-SPATIAL SKETCHPAD encodes and stores visually, limited in capacity and duration. You can illustrate working memory works by asking how many windows in your house? and the PHONOLOGICAL STOREwhich also has a limited capacity.
LEVELS OF PROCESSING THEORY Craik and Lockhart (1972) suggested that information can be processed at different levels. Visual by appearance eg: starts with capital letter SHALLOW PROCESSINGNeeds less thinking The deeper we process the information the better we remember it in LTM. Phonetic by sound, eg: rhyme’s with ….? DEEP PROCESSINGMore thinking involved Semantic by meaning, eg: associated with? ELABORATION is 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.
Evaluating Models of Memory + 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. Multi Store + 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 Levels of processing + 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 Working Memory
Types of Long Term Memory Our “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. Procedural 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. Semantic Our “episodes of life” or autobiographical memory, eg: last holiday, sixteenth birthday. Includes Flashbulb Memories which are vivid, emotive memories – ( eg 9/11 ). Episodic 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.
In which of the three stages of memory could forgetting occur? ENCODING STORAGE RETRIEVAL Explaining Forgetting From introspection suggest some factors that could lead to forgetting ? • Not really wanting to recall • Time • Brain Damage • Confusing information • Alcohol etc. • Too much stuff to remember 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.
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. The simple idea that memories are lost over time is called Ebbinghaus found that his memory decayed over time, called the “FORGETTING CURVE”. However he also found that it did not take so long to remember these items the second time around. He called this his “SAVINGS” RECALL % TRACE DECAY TIME = DAYS 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.
Interference task practice – count back in three’s from 333. Student Exercise MemEx1 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. L Z M , P V Q, X F D 763 STOP! WRITE NOW! B F Y , G Z J, P D L 435 STOP!WRITE NOW! K M R , H G Y, J T Z 917 STOP!WRITE NOW! M Q L , T L Y, F R N 329 STOP!WRITE NOW! 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.
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 .. Trace Decay OR Interference? 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.
INTERFERENCE RETROACTIVE For example you are learning Spanish this year, last year you leant French. Where information learnt earlier interferes with that learnt later. Where information learnt later interferes with that learnt first. PROACTIVE Qu. What is it if John calls his current girlfriend by the name of his ex? 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?
This theory assumes that a memory store has a limited capacity, so which types of memory will it apply to? Is the simple idea that new memories will replace old ones Miller (1956) found that when STM was full up (5 – 9 items) new material would push out the old. NEW INFORMATION INPUT OTHER INFORMATION IS LOST S.T.M. 7+-2 items DISPLACEMENT Also Sperling (1960) found that SENSORY MEMORY also has a very limited capacity so this theory would also explain forgetting here but- 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.
Which theory best explains the Serial Position Effect? 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? INTERFERENCE? Serial Position Curve Primacy Effect Recency Effect Retro-active Interference only Pro-active Interference only Both Pro-active & Retro-active 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 Consolidation L.T.M. S.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 Failure Also called Cue Dependant Forgetting “Tip of the Tongue” is a common experience when we simply need the right clue (or Cue) to help us recall something. The cue usually relates to the conditions of encoding, in semantic memory it often organisational – eg: categories. State Dependant forgetting Is when your internal state, mood or condition at the time of encoding information provides a cue to remembering it. Context Dependant forgetting WORDS WORDS WORKS 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.
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 .. Repression 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.